Лабораторный опыт 2, страница 71 - 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 1. Первоначальные химические понятия. Параграф 21. Типы химических реакций. Подумай, ответь, выполни... - страница 71.

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                              "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 {#1069
                      #items: array:1 [
                        0 => App\Models\Term {#1070
                          #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
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "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 {#1071
                      #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 {#1072
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1073
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1074
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/8-klass/himiya/rudzitis-uchebnik-2019"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1075
                      #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 {#1050}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1051}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1053}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1055}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1057}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1058}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1060}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1062}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1064}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1065}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1066}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1067}
                    "field_publication_number" => "11"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1069}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1071}
                    "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 {#1072}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1073}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1074}
                    "field_url" => "/8-klass/himiya/rudzitis-uchebnik-2019"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1075}
                    "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 {#1076
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1367111
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Первоначальные химические понятия"
            "field_branch_order" => "1"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1049}
            "field_page_start" => "4"
            "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 {#1078}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1076}
          ]
          #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 {#1105
      #items: array:3 [
        0 => App\Models\Branch {#1115
          #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" => 1367111
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Первоначальные химические понятия"
            "field_branch_order" => "1"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1116
              #items: array:1 [
                0 => App\Models\Term {#1046}
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "4"
            "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 {#1117
              #items: array:1 [
                0 => App\Models\Book {#1048}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1118
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1367111
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Первоначальные химические понятия"
            "field_branch_order" => "1"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1116}
            "field_page_start" => "4"
            "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 {#1117}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1118}
          ]
          #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 {#1119
          #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" => 1367166
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Типы химических реакций"
            "field_branch_order" => "21"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1123
              #items: array:1 [
                0 => App\Models\Term {#1120
                  #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" => "69"
            "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 {#1122
              #items: array:1 [
                0 => App\Models\Book {#1048}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1121
              #items: array:1 [
                0 => App\Models\Branch {#1044}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1367166
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Типы химических реакций"
            "field_branch_order" => "21"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1123}
            "field_page_start" => "69"
            "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 {#1122}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1121}
          ]
          #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 {#1124
          #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" => 1367167
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Подумай, ответь, выполни..."
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1125
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "69"
            "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 {#1126
              #items: array:1 [
                0 => App\Models\Book {#1048}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1135
              #items: array:1 [
                0 => App\Models\Branch {#1134
                  #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" => 1367166
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Типы химических реакций"
                    "field_branch_order" => "21"
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1136
                      #items: array:1 [
                        0 => App\Models\Term {#1120}
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_page_start" => "69"
                    "field_branch_display" => "0"
                    "field_branch_expanded" => "0"
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            "text" => "<p><strong>Лабораторный опыт 2.</strong> Реакция замещения меди железом</p><p>Налейте в пробирку (примерно на $1/4$ её объёма) раствор хлорида меди(II) и опустите в него очищенный железный гвоздь (или железные опилки): поверхность гвоздя покрывается медью, а цвет раствора поменяется со временем с голубого на зеленоватый.</p><p>🔵 Какие признаки свидетельствуют о том, что произошла химическая реакция? Как вы думаете, почему поменялся цвет раствора? Объясните эту реакцию с точки зрения атомно-молекулярного учения.</p>"
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            "task" => array:2 [
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              "type" => "task"
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            "text" => "<p><strong>Лабораторный опыт 2.</strong> Реакция замещения меди железом</p><p>Налейте в пробирку (примерно на $1/4$ её объёма) раствор хлорида меди(II) и опустите в него очищенный железный гвоздь (или железные опилки): поверхность гвоздя покрывается медью, а цвет раствора поменяется со временем с голубого на зеленоватый.</p><p>🔵 Какие признаки свидетельствуют о том, что произошла химическая реакция? Как вы думаете, почему поменялся цвет раствора? Объясните эту реакцию с точки зрения атомно-молекулярного учения.</p>"
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            "text" => "<p><strong>Какие признаки свидетельствуют о том, что произошла химическая реакция?</strong></p><p>О том, что произошла химическая реакция, свидетельствуют следующие наблюдаемые признаки:</p><ol><li>Изменение цвета поверхности железного гвоздя: на нем образуется налет красного цвета, который представляет собой металлическую медь. Это указывает на образование нового вещества.</li><li>Изменение цвета раствора: исходный голубой цвет раствора хлорида меди(II) постепенно сменяется на зеленоватый. Это говорит об изменении химического состава раствора.</li></ol><p><strong>Ответ:</strong> Признаками химической реакции являются образование осадка (меди на гвозде) и изменение цвета раствора.</p><p><strong>Как вы думаете, почему поменялся цвет раствора?</strong></p><p>Цвет раствора изменился, потому что изменился его ионный состав. Исходный голубой цвет был обусловлен присутствием в растворе гидратированных ионов меди(II) ($Cu^{2+}$). В ходе реакции железо вытесняет медь из раствора соли, и в растворе появляются гидратированные ионы железа(II) ($Fe^{2+}$), которые придают раствору зеленоватый оттенок. Концентрация ионов меди ($Cu^{2+}$) уменьшается, а концентрация ионов железа ($Fe^{2+}$) увеличивается, что и приводит к наблюдаемому изменению цвета с голубого на зеленоватый.</p><p><strong>Ответ:</strong> Цвет раствора поменялся, так как ионы меди($Cu^{2+}$), придающие раствору голубой цвет, были заменены на ионы железа($Fe^{2+}$), придающие раствору зеленоватый цвет.</p><p><strong>Объясните эту реакцию с точки зрения атомно-молекулярного учения.</strong></p><p>С точки зрения атомно-молекулярного учения, химическая реакция представляет собой перегруппировку атомов с образованием новых веществ. В данном опыте происходит следующее:</p><p><strong>1.</strong> Исходные вещества состоят из атомов железа ($\text{Fe}$), образующих кристаллическую решетку гвоздя, и ионов меди ($Cu^{2+}$) и хлорид-ионов ($Cl^{-}$), находящихся в водном растворе (вещество — хлорид меди(II) $CuCl_2$).</p><p><strong>2.</strong> При контакте гвоздя с раствором атомы более активного металла — железа ($\text{Fe}$) — взаимодействуют с ионами менее активного металла — меди ($Cu^{2+}$).</p><p><strong>3.</strong> Каждый атом железа отдает два электрона и превращается в положительно заряженный ион железа ($Fe^{2+}$), который переходит из гвоздя в раствор.</p><p><strong>4.</strong> В это же время ион меди ($Cu^{2+}$) из раствора принимает два электрона и превращается в нейтральный атом меди ($\text{Cu}$). Атомы меди оседают на поверхности железного гвоздя, образуя красный налет.</p><p>Таким образом, атомы одного элемента (железа) замещают атомы другого элемента (меди) в его соединении. Хлорид-ионы ($Cl^{-}$) в реакции не участвуют и остаются в растворе.</p><p>Уравнение реакции в молекулярном виде:</p><p>$Fe + CuCl_2 \rightarrow FeCl_2 + Cu$</p><p>Сокращенное ионное уравнение, показывающее суть процесса:</p><p>$Fe^0 + Cu^{2+} \rightarrow Fe^{2+} + Cu^0$</p><p><strong>Ответ:</strong> Реакция заключается в том, что атомы железа отдают электроны ионам меди. В результате образуются ионы железа, переходящие в раствор, и атомы меди, оседающие на гвозде. Происходит перегруппировка частиц: атомы железа замещают ионы меди в растворе соли.</p>"
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            "text" => "<p><strong>Какие признаки свидетельствуют о том, что произошла химическая реакция?</strong></p><p>О том, что произошла химическая реакция, свидетельствуют следующие наблюдаемые признаки:</p><ol><li>Изменение цвета поверхности железного гвоздя: на нем образуется налет красного цвета, который представляет собой металлическую медь. Это указывает на образование нового вещества.</li><li>Изменение цвета раствора: исходный голубой цвет раствора хлорида меди(II) постепенно сменяется на зеленоватый. Это говорит об изменении химического состава раствора.</li></ol><p><strong>Ответ:</strong> Признаками химической реакции являются образование осадка (меди на гвозде) и изменение цвета раствора.</p><p><strong>Как вы думаете, почему поменялся цвет раствора?</strong></p><p>Цвет раствора изменился, потому что изменился его ионный состав. Исходный голубой цвет был обусловлен присутствием в растворе гидратированных ионов меди(II) ($Cu^{2+}$). В ходе реакции железо вытесняет медь из раствора соли, и в растворе появляются гидратированные ионы железа(II) ($Fe^{2+}$), которые придают раствору зеленоватый оттенок. Концентрация ионов меди ($Cu^{2+}$) уменьшается, а концентрация ионов железа ($Fe^{2+}$) увеличивается, что и приводит к наблюдаемому изменению цвета с голубого на зеленоватый.</p><p><strong>Ответ:</strong> Цвет раствора поменялся, так как ионы меди($Cu^{2+}$), придающие раствору голубой цвет, были заменены на ионы железа($Fe^{2+}$), придающие раствору зеленоватый цвет.</p><p><strong>Объясните эту реакцию с точки зрения атомно-молекулярного учения.</strong></p><p>С точки зрения атомно-молекулярного учения, химическая реакция представляет собой перегруппировку атомов с образованием новых веществ. В данном опыте происходит следующее:</p><p><strong>1.</strong> Исходные вещества состоят из атомов железа ($\text{Fe}$), образующих кристаллическую решетку гвоздя, и ионов меди ($Cu^{2+}$) и хлорид-ионов ($Cl^{-}$), находящихся в водном растворе (вещество — хлорид меди(II) $CuCl_2$).</p><p><strong>2.</strong> При контакте гвоздя с раствором атомы более активного металла — железа ($\text{Fe}$) — взаимодействуют с ионами менее активного металла — меди ($Cu^{2+}$).</p><p><strong>3.</strong> Каждый атом железа отдает два электрона и превращается в положительно заряженный ион железа ($Fe^{2+}$), который переходит из гвоздя в раствор.</p><p><strong>4.</strong> В это же время ион меди ($Cu^{2+}$) из раствора принимает два электрона и превращается в нейтральный атом меди ($\text{Cu}$). Атомы меди оседают на поверхности железного гвоздя, образуя красный налет.</p><p>Таким образом, атомы одного элемента (железа) замещают атомы другого элемента (меди) в его соединении. Хлорид-ионы ($Cl^{-}$) в реакции не участвуют и остаются в растворе.</p><p>Уравнение реакции в молекулярном виде:</p><p>$Fe + CuCl_2 \rightarrow FeCl_2 + Cu$</p><p>Сокращенное ионное уравнение, показывающее суть процесса:</p><p>$Fe^0 + Cu^{2+} \rightarrow Fe^{2+} + Cu^0$</p><p><strong>Ответ:</strong> Реакция заключается в том, что атомы железа отдают электроны ионам меди. В результате образуются ионы железа, переходящие в раствор, и атомы меди, оседающие на гвозде. Происходит перегруппировка частиц: атомы железа замещают ионы меди в растворе соли.</p>"
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Лабораторный опыт 2 (с. 71)
Условие. Лабораторный опыт 2 (с. 71)
скриншот условия
Химия, 8 класс Учебник, автор: Рудзитис Гунтис Екабович, издательство Просвещение, Москва, 2019 - 2022, страница 71, Условие

Лабораторный опыт 2. Реакция замещения меди железом

Налейте в пробирку (примерно на $1/4$ её объёма) раствор хлорида меди(II) и опустите в него очищенный железный гвоздь (или железные опилки): поверхность гвоздя покрывается медью, а цвет раствора поменяется со временем с голубого на зеленоватый.

🔵 Какие признаки свидетельствуют о том, что произошла химическая реакция? Как вы думаете, почему поменялся цвет раствора? Объясните эту реакцию с точки зрения атомно-молекулярного учения.

Решение. Лабораторный опыт 2 (с. 71)
Химия, 8 класс Учебник, автор: Рудзитис Гунтис Екабович, издательство Просвещение, Москва, 2019 - 2022, страница 71, Решение
Решение 2. Лабораторный опыт 2 (с. 71)

Какие признаки свидетельствуют о том, что произошла химическая реакция?

О том, что произошла химическая реакция, свидетельствуют следующие наблюдаемые признаки:

  1. Изменение цвета поверхности железного гвоздя: на нем образуется налет красного цвета, который представляет собой металлическую медь. Это указывает на образование нового вещества.
  2. Изменение цвета раствора: исходный голубой цвет раствора хлорида меди(II) постепенно сменяется на зеленоватый. Это говорит об изменении химического состава раствора.

Ответ: Признаками химической реакции являются образование осадка (меди на гвозде) и изменение цвета раствора.

Как вы думаете, почему поменялся цвет раствора?

Цвет раствора изменился, потому что изменился его ионный состав. Исходный голубой цвет был обусловлен присутствием в растворе гидратированных ионов меди(II) ($Cu^{2+}$). В ходе реакции железо вытесняет медь из раствора соли, и в растворе появляются гидратированные ионы железа(II) ($Fe^{2+}$), которые придают раствору зеленоватый оттенок. Концентрация ионов меди ($Cu^{2+}$) уменьшается, а концентрация ионов железа ($Fe^{2+}$) увеличивается, что и приводит к наблюдаемому изменению цвета с голубого на зеленоватый.

Ответ: Цвет раствора поменялся, так как ионы меди($Cu^{2+}$), придающие раствору голубой цвет, были заменены на ионы железа($Fe^{2+}$), придающие раствору зеленоватый цвет.

Объясните эту реакцию с точки зрения атомно-молекулярного учения.

С точки зрения атомно-молекулярного учения, химическая реакция представляет собой перегруппировку атомов с образованием новых веществ. В данном опыте происходит следующее:

1. Исходные вещества состоят из атомов железа ($\text{Fe}$), образующих кристаллическую решетку гвоздя, и ионов меди ($Cu^{2+}$) и хлорид-ионов ($Cl^{-}$), находящихся в водном растворе (вещество — хлорид меди(II) $CuCl_2$).

2. При контакте гвоздя с раствором атомы более активного металла — железа ($\text{Fe}$) — взаимодействуют с ионами менее активного металла — меди ($Cu^{2+}$).

3. Каждый атом железа отдает два электрона и превращается в положительно заряженный ион железа ($Fe^{2+}$), который переходит из гвоздя в раствор.

4. В это же время ион меди ($Cu^{2+}$) из раствора принимает два электрона и превращается в нейтральный атом меди ($\text{Cu}$). Атомы меди оседают на поверхности железного гвоздя, образуя красный налет.

Таким образом, атомы одного элемента (железа) замещают атомы другого элемента (меди) в его соединении. Хлорид-ионы ($Cl^{-}$) в реакции не участвуют и остаются в растворе.

Уравнение реакции в молекулярном виде:

$Fe + CuCl_2 \rightarrow FeCl_2 + Cu$

Сокращенное ионное уравнение, показывающее суть процесса:

$Fe^0 + Cu^{2+} \rightarrow Fe^{2+} + Cu^0$

Ответ: Реакция заключается в том, что атомы железа отдают электроны ионам меди. В результате образуются ионы железа, переходящие в раствор, и атомы меди, оседающие на гвозде. Происходит перегруппировка частиц: атомы железа замещают ионы меди в растворе соли.

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