Номер 2, страница 83 - гдз по химии 8 класс учебник Рудзитис

Химия, 8 класс Учебник, автор: Рудзитис Гунтис Екабович, издательство Просвещение, Москва, 2019 - 2022

Авторы: Рудзитис Г. Е.

Тип: Учебник

Издательство: Просвещение

Год издания: 2019 - 2022

ISBN: 978-5-09-088251-4

Допущено Министерством просвещения Российской Федерации

Глава 2. Кислород. Горение. Параграф 24. Применение кислорода. Круговорот кислорода в природе. Тестовые задания - номер 2, страница 83.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
  #connection: "mysql"
  #table: "tasks"
  #primaryKey: "id"
  #keyType: "int"
  +incrementing: true
  #with: []
  #withCount: []
  +preventsLazyLoading: false
  #perPage: 15
  +exists: true
  +wasRecentlyCreated: false
  #escapeWhenCastingToString: false
  #attributes: array:24 [
    "id" => 1367452
    "created_at" => "2026-04-10 13:58:26"
    "updated_at" => null
    "field_page_start" => "83"
    "field_page_end" => null
    "field_url" => "/8-klass/himiya/rudzitis-uchebnik-2019/24-4-2"
    "field_display_title" => "2"
    "field_outside_task" => null
    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1037
      #items: array:1 [
        0 => App\Models\Term {#1036
          #connection: "mysql"
          #table: "terms"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: false
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #original: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
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          #dateFormat: null
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          +timestamps: true
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          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "field_metatags_title" => null
    "field_metatags_description" => null
    "field_h1" => null
    "field_description_top" => null
    "field_description_bottom" => null
    "field_match" => null
    "breadcrumbs" => []
    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1035
      #items: []
      #escapeWhenCastingToString: false
    }
    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1046
      #items: array:1 [
        0 => App\Models\Branch {#1045
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
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          #attributes: array:24 [
            "id" => 1367168
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Кислород. Горение"
            "field_branch_order" => "2"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1050
              #items: array:1 [
                0 => App\Models\Term {#1047
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  #attributes: array:7 [
                    "id" => 29
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Глава"
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                      "field_dative_case" => "Главе"
                      "field_genitive_case" => "Главы"
                      "field_nominative_case" => "Глава"
                      "field_prepositional_case" => "Главе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => null
                  ]
                  #original: array:7 [
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                      "field_genitive_case" => "Главы"
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                    ]
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                  ]
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              #escapeWhenCastingToString: false
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            "field_display_branch_page" => "1"
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            "field_navigation_title" => null
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1079
              #items: array:1 [
                0 => App\Models\Book {#1049
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
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                  #perPage: 15
                  +exists: true
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                  #escapeWhenCastingToString: false
                  #attributes: array:50 [
                    "id" => 524
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1051
                      #items: array:1 [
                        0 => App\Models\Term {#1048
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6495
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Химия"
                            "field_abbreviated_name" => null
                            "field_cases" => array:6 [
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                              "field_creative_case" => "химией"
                              "field_dative_case" => "химии"
                              "field_genitive_case" => "химии"
                              "field_nominative_case" => "химия"
                              "field_prepositional_case" => "химии"
                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "himiya"
                          ]
                          #original: array:10 [
                            "id" => 6495
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Химия"
                            "field_abbreviated_name" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "химию"
                              "field_creative_case" => "химией"
                              "field_dative_case" => "химии"
                              "field_genitive_case" => "химии"
                              "field_nominative_case" => "химия"
                              "field_prepositional_case" => "химии"
                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "himiya"
                          ]
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                          #hidden: []
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                            0 => "*"
                          ]
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                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1052
                      #items: array:1 [
                        0 => App\Models\Term {#1053
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
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                          #perPage: 15
                          +exists: true
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                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 5457
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "8"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "восьмой"
                              "field_creative_case" => "восьмым"
                              "field_dative_case" => "восьмому"
                              "field_genitive_case" => "восьмого"
                              "field_nominative_case" => "восьмой"
                              "field_prepositional_case" => "восьмом"
                            ]
                            "field_translit" => "vosmoj"
                          ]
                          #original: array:6 [
                            "id" => 5457
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "8"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "восьмой"
                              "field_creative_case" => "восьмым"
                              "field_dative_case" => "восьмому"
                              "field_genitive_case" => "восьмого"
                              "field_nominative_case" => "восьмой"
                              "field_prepositional_case" => "восьмом"
                            ]
                            "field_translit" => "vosmoj"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
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                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1054
                      #items: array:1 [
                        0 => App\Models\Term {#1055
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #with: []
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                          #escapeWhenCastingToString: false
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_cases" => null
                            "field_translit" => "prosveschenie"
                          ]
                          #original: array:6 [
                            "id" => 5153
                            "created_at" => "2026-04-10 13:58:26"
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                          ]
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                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1056
                      #items: array:1 [
                        0 => App\Models\Term {#1057
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #with: []
                          #withCount: []
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                            "id" => 5630
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Рудзитис"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Гунтис"
                            "field_patronymic" => "Екабович"
                            "field_surname_rp" => null
                          ]
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                            "id" => 5630
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_bio" => null
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                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Гунтис"
                            "field_patronymic" => "Екабович"
                            "field_surname_rp" => null
                          ]
                          #changes: []
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                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1058
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1059
                      #items: array:1 [
                        0 => App\Models\Term {#1060
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #attributes: array:10 [
                            "id" => 6671
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [
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                              "field_prepositional_case" => "учебнике"
                            ]
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                            "field_translit" => "uchebnik"
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                    "field_country" => Illuminate\Database\Eloquent\Collection {#1061
                      #items: array:1 [
                        0 => App\Models\Term {#1062
                          #connection: "mysql"
                          #table: "terms"
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                    "field_city" => Illuminate\Database\Eloquent\Collection {#1063
                      #items: array:1 [
                        0 => App\Models\Term {#1064
                          #connection: "mysql"
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            ]
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                          ]
                          #original: array:6 [
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                            "updated_at" => null
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                            "field_translit" => "moskva"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1065
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1066
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1067
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1068
                      #items: array:1 [
                        0 => App\Models\Term {#1069
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6706
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (старый)"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_color" => null
                            "field_end_year" => "2022"
                            "field_start_year" => "2019"
                            "field_translit" => "fgos-old"
                            "field_type" => null
                          ]
                          #original: array:10 [
                            "id" => 6706
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (старый)"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_color" => null
                            "field_end_year" => "2022"
                            "field_start_year" => "2019"
                            "field_translit" => "fgos-old"
                            "field_type" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => "11"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1070
                      #items: array:1 [
                        0 => App\Models\Term {#1071
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "stereotipnoe"
                          ]
                          #original: array:6 [
                            "id" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                               …4
                            ]
                            "field_translit" => "stereotipnoe"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1072
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => "2022"
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для общеобразовательных организаций"
                    "field_allowed" => "Допущено Министерством просвещения Российской Федерации"
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "418"
                    "field_priority" => "8"
                    "field_default_folder" => "/himiya_08/rudzitis-u/"
                    "field_isbn" => "978-5-09-088251-4"
                    "field_cover" => array:1 [
                      0 => "/media/himiya_08/rudzitis-u/covers/cover1.webp?ts=1743939572"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/himiya_08/rudzitis-u/covers/cover1.webp?ts=1743939572"
                        "alt" => ""
                        "width" => "1444"
                        "height" => "2154"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1073
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1074
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1075
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/8-klass/himiya/rudzitis-uchebnik-2019"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1076
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 379
                      "subject" => 558
                      "class_subject" => 498
                    ]
                  ]
                  #original: array:50 [
                    "id" => 524
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1051}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1052}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1054}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1056}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1058}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1059}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1061}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1063}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1065}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1066}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1067}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1068}
                    "field_publication_number" => "11"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1070}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1072}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => "2022"
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для общеобразовательных организаций"
                    "field_allowed" => "Допущено Министерством просвещения Российской Федерации"
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "418"
                    "field_priority" => "8"
                    "field_default_folder" => "/himiya_08/rudzitis-u/"
                    "field_isbn" => "978-5-09-088251-4"
                    "field_cover" => array:1 [
                      0 => "/media/himiya_08/rudzitis-u/covers/cover1.webp?ts=1743939572"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/himiya_08/rudzitis-u/covers/cover1.webp?ts=1743939572"
                        "alt" => ""
                        "width" => "1444"
                        "height" => "2154"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1073}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1074}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1075}
                    "field_url" => "/8-klass/himiya/rudzitis-uchebnik-2019"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1076}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 379
                      "subject" => 558
                      "class_subject" => 498
                    ]
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1077
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1367168
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Кислород. Горение"
            "field_branch_order" => "2"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1050}
            "field_page_start" => "72"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1079}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1077}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1106
      #items: array:3 [
        0 => App\Models\Branch {#1116
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1367168
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Кислород. Горение"
            "field_branch_order" => "2"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1117
              #items: array:1 [
                0 => App\Models\Term {#1047}
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "72"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1118
              #items: array:1 [
                0 => App\Models\Book {#1049}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1119
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1367168
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Кислород. Горение"
            "field_branch_order" => "2"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1117}
            "field_page_start" => "72"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1118}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1119}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1120
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1367175
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Применение кислорода. Круговорот кислорода в природе"
            "field_branch_order" => "24"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1124
              #items: array:1 [
                0 => App\Models\Term {#1121
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Параграф"
                      "field_creative_case" => "Параграфом"
                      "field_dative_case" => "Параграфу"
                      "field_genitive_case" => "Параграфа"
                      "field_nominative_case" => "Параграф"
                      "field_prepositional_case" => "Параграфе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #original: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Параграф"
                      "field_creative_case" => "Параграфом"
                      "field_dative_case" => "Параграфу"
                      "field_genitive_case" => "Параграфа"
                      "field_nominative_case" => "Параграф"
                      "field_prepositional_case" => "Параграфе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "81"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1123
              #items: array:1 [
                0 => App\Models\Book {#1049}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1122
              #items: array:1 [
                0 => App\Models\Branch {#1045}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1367175
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Применение кислорода. Круговорот кислорода в природе"
            "field_branch_order" => "24"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1124}
            "field_page_start" => "81"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1123}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1122}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1125
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1367177
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Тестовые задания"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1126
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "83"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
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            "book" => Illuminate\Database\Eloquent\Collection {#1127
              #items: array:1 [
                0 => App\Models\Book {#1049}
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            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1136
              #items: array:1 [
                0 => App\Models\Branch {#1135
                  #connection: "mysql"
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                    "created_at" => "2026-04-10 13:58:26"
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                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1139
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                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1094
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                    "field_solution_author" => "Автор"
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                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1093
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                    "id" => 4499
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                    "title" => "Условие"
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                    "field_solution_author" => "Автор"
                    "field_moderator" => "pasha"
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                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1093}
                    "field_comment" => null
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                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1090}
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                  ]
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              ]
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            "task" => array:2 [
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              "type" => "task"
            ]
            "text" => "<p><strong>2.</strong> Массовая доля химического элемента фосфора в оксиде фосфора(V) составляет</p><p><strong>1)</strong> 19,2%</p><p><strong>2)</strong> 36,4%</p><p><strong>3)</strong> 43,7%</p><p><strong>4)</strong> 100%</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "2-1.jpg"
                "alt" => null
                "width" => "731"
                "height" => 132
                "path" => "/media/himiya_08/rudzitis-u/0-24-4/2-1.webp?ts=1757414610"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1579789
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1089}
            "task" => array:2 [
              "refs" => "1367452"
              "type" => "task"
            ]
            "text" => "<p><strong>2.</strong> Массовая доля химического элемента фосфора в оксиде фосфора(V) составляет</p><p><strong>1)</strong> 19,2%</p><p><strong>2)</strong> 36,4%</p><p><strong>3)</strong> 43,7%</p><p><strong>4)</strong> 100%</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "2-1.jpg"
                "alt" => null
                "width" => "731"
                "height" => 132
                "path" => "/media/himiya_08/rudzitis-u/0-24-4/2-1.webp?ts=1757414610"
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          +timestamps: true
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          #hidden: []
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            0 => "*"
          ]
        }
        1 => App\Models\Element {#1091
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
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          #attributes: array:6 [
            "id" => 1579884
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1078
              #items: array:1 [
                0 => App\Models\Edition {#1088
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 4500
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1087
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
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                    "field_content_type" => "free"
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                    "field_page_content_mode" => ""
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                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Ларикова"
                    "field_moderator" => "pasha"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1085
                      #items: []
                      #escapeWhenCastingToString: false
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                    "field_comment" => null
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                      #items: []
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                      #items: []
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                    "id" => 4500
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1087}
                    "field_content_type" => "free"
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                    "field_solution_author" => "Ларикова"
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                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1085}
                    "field_comment" => null
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                  ]
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                "width" => "929"
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            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
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              "refs" => "1367452"
              "type" => "task"
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        2 => App\Models\Element {#1081
          #connection: "mysql"
          #table: "elements"
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            "id" => 1740171
            "created_at" => "2026-04-10 13:58:26"
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            "edition" => Illuminate\Database\Eloquent\Collection {#1112
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                0 => App\Models\Edition {#1082
                  #connection: "mysql"
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                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  #attributes: array:21 [
                    "id" => 6342
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 2"
                    "field_order" => "3"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1043
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
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                    "field_content_type" => "free"
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                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
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                      #items: []
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                    "id" => 6342
                    "created_at" => "2026-04-10 13:58:26"
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                    "title" => "Решение 2"
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                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
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                  ]
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                    0 => "*"
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              ]
              #escapeWhenCastingToString: false
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            "task" => array:2 [
              "refs" => "1367452"
              "type" => "task"
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            "text" => "<p><strong>Дано:</strong></p><p>Оксид фосфора(V)</p><p><strong>Найти:</strong></p><p>Массовую долю фосфора ($ω(P)$) - ?</p><p><strong>Решение:</strong></p><p><strong>1.</strong> Определим химическую формулу оксида фосфора(V). Валентность фосфора в этом соединении равна V, а валентность кислорода постоянна и равна II. Чтобы составить формулу, найдем наименьшее общее кратное валентностей (5 и 2), которое равно 10. Затем определим индексы, разделив наименьшее общее кратное на валентность каждого элемента: для фосфора $10 / 5 = 2$, для кислорода $10 / 2 = 5$. Таким образом, формула оксида фосфора(V) — $P_2O_5$.</p><p><strong>2.</strong> Массовая доля элемента в веществе вычисляется по формуле:</p><p>$ω(Э) = \frac{n \cdot Ar(Э)}{Mr(вещества)} \cdot 100\%$</p><p>где $ω(Э)$ — массовая доля элемента, $\text{n}$ — число атомов элемента в формульной единице, $Ar(Э)$ — относительная атомная масса элемента, $Mr(вещества)$ — относительная молекулярная масса вещества.</p><p><strong>3.</strong> Найдем относительные атомные массы элементов по Периодической системе Д.И. Менделеева (округляя до целых чисел):</p><p>$Ar(P) = 31$</p><p>$Ar(O) = 16$</p><p><strong>4.</strong> Рассчитаем относительную молекулярную массу оксида фосфора(V) ($P_2O_5$):</p><p>$Mr(P_2O_5) = 2 \cdot Ar(P) + 5 \cdot Ar(O) = 2 \cdot 31 + 5 \cdot 16 = 62 + 80 = 142$</p><p><strong>5.</strong> Рассчитаем массовую долю фосфора в оксиде фосфора(V). В одной формульной единице $P_2O_5$ содержится 2 атома фосфора:</p><p>$ω(P) = \frac{2 \cdot Ar(P)}{Mr(P_2O_5)} \cdot 100\% = \frac{2 \cdot 31}{142} \cdot 100\% = \frac{62}{142} \cdot 100\% \approx 0,4366 \cdot 100\% \approx 43,7\%$</p><p>Полученное значение соответствует варианту ответа 3).</p><p><strong>Ответ:</strong> 43,7%.</p>"
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            "text" => "<p><strong>Дано:</strong></p><p>Оксид фосфора(V)</p><p><strong>Найти:</strong></p><p>Массовую долю фосфора ($ω(P)$) - ?</p><p><strong>Решение:</strong></p><p><strong>1.</strong> Определим химическую формулу оксида фосфора(V). Валентность фосфора в этом соединении равна V, а валентность кислорода постоянна и равна II. Чтобы составить формулу, найдем наименьшее общее кратное валентностей (5 и 2), которое равно 10. Затем определим индексы, разделив наименьшее общее кратное на валентность каждого элемента: для фосфора $10 / 5 = 2$, для кислорода $10 / 2 = 5$. Таким образом, формула оксида фосфора(V) — $P_2O_5$.</p><p><strong>2.</strong> Массовая доля элемента в веществе вычисляется по формуле:</p><p>$ω(Э) = \frac{n \cdot Ar(Э)}{Mr(вещества)} \cdot 100\%$</p><p>где $ω(Э)$ — массовая доля элемента, $\text{n}$ — число атомов элемента в формульной единице, $Ar(Э)$ — относительная атомная масса элемента, $Mr(вещества)$ — относительная молекулярная масса вещества.</p><p><strong>3.</strong> Найдем относительные атомные массы элементов по Периодической системе Д.И. Менделеева (округляя до целых чисел):</p><p>$Ar(P) = 31$</p><p>$Ar(O) = 16$</p><p><strong>4.</strong> Рассчитаем относительную молекулярную массу оксида фосфора(V) ($P_2O_5$):</p><p>$Mr(P_2O_5) = 2 \cdot Ar(P) + 5 \cdot Ar(O) = 2 \cdot 31 + 5 \cdot 16 = 62 + 80 = 142$</p><p><strong>5.</strong> Рассчитаем массовую долю фосфора в оксиде фосфора(V). В одной формульной единице $P_2O_5$ содержится 2 атома фосфора:</p><p>$ω(P) = \frac{2 \cdot Ar(P)}{Mr(P_2O_5)} \cdot 100\% = \frac{2 \cdot 31}{142} \cdot 100\% = \frac{62}{142} \cdot 100\% \approx 0,4366 \cdot 100\% \approx 43,7\%$</p><p>Полученное значение соответствует варианту ответа 3).</p><p><strong>Ответ:</strong> 43,7%.</p>"
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№2 (с. 83)
Условие. №2 (с. 83)
скриншот условия
Химия, 8 класс Учебник, автор: Рудзитис Гунтис Екабович, издательство Просвещение, Москва, 2019 - 2022, страница 83, номер 2, Условие

2. Массовая доля химического элемента фосфора в оксиде фосфора(V) составляет

1) 19,2%

2) 36,4%

3) 43,7%

4) 100%

Решение. №2 (с. 83)
Химия, 8 класс Учебник, автор: Рудзитис Гунтис Екабович, издательство Просвещение, Москва, 2019 - 2022, страница 83, номер 2, Решение
Решение 2. №2 (с. 83)

Дано:

Оксид фосфора(V)

Найти:

Массовую долю фосфора ($ω(P)$) - ?

Решение:

1. Определим химическую формулу оксида фосфора(V). Валентность фосфора в этом соединении равна V, а валентность кислорода постоянна и равна II. Чтобы составить формулу, найдем наименьшее общее кратное валентностей (5 и 2), которое равно 10. Затем определим индексы, разделив наименьшее общее кратное на валентность каждого элемента: для фосфора $10 / 5 = 2$, для кислорода $10 / 2 = 5$. Таким образом, формула оксида фосфора(V) — $P_2O_5$.

2. Массовая доля элемента в веществе вычисляется по формуле:

$ω(Э) = \frac{n \cdot Ar(Э)}{Mr(вещества)} \cdot 100\%$

где $ω(Э)$ — массовая доля элемента, $\text{n}$ — число атомов элемента в формульной единице, $Ar(Э)$ — относительная атомная масса элемента, $Mr(вещества)$ — относительная молекулярная масса вещества.

3. Найдем относительные атомные массы элементов по Периодической системе Д.И. Менделеева (округляя до целых чисел):

$Ar(P) = 31$

$Ar(O) = 16$

4. Рассчитаем относительную молекулярную массу оксида фосфора(V) ($P_2O_5$):

$Mr(P_2O_5) = 2 \cdot Ar(P) + 5 \cdot Ar(O) = 2 \cdot 31 + 5 \cdot 16 = 62 + 80 = 142$

5. Рассчитаем массовую долю фосфора в оксиде фосфора(V). В одной формульной единице $P_2O_5$ содержится 2 атома фосфора:

$ω(P) = \frac{2 \cdot Ar(P)}{Mr(P_2O_5)} \cdot 100\% = \frac{2 \cdot 31}{142} \cdot 100\% = \frac{62}{142} \cdot 100\% \approx 0,4366 \cdot 100\% \approx 43,7\%$

Полученное значение соответствует варианту ответа 3).

Ответ: 43,7%.

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