题目

请用所学化学知识解释下列事实：（1）洗涤剂能除去油污，是因为它具有 功能．（2）金秋时节，古城开封处处都能闻到怡人的菊花香气 ．（3）镁条在空气中燃烧后，生成物的质量比原来镁条的质量增大 ．（4）牛奶在夏天比冬天更容易变酸 ． 答案：【1】乳化【2】分子是不断运动的，菊花中含有香味的分子不断运动，向四周扩散，所以人们能闻到香味【3】反应物为镁条和空气中的氧气，生成物为氧化镁，根据质量守恒定律，氧化镁的质量等于参加反应的镁条和氧气的质量之和，所以比原来镁条的质量增大了【4】温度越高，化学反应速率越快 Zhao Lei's family is very big B Come and look at the photo. It's an American family. The woman in the middle is Beth White. She is a teacher. The old woman on her right is her mother. She is Mrs White. The man on her left is her father,Mr White. He is an artist (艺术家) .The other young woman is Doris White. She is her youn?ger sister. Doris White has two children. They are students. Leo Bush is her son and May Bush is her daughter. May sits next to her grandmother.(   ) 31. This is family photo.   A. an American   B. an English   C. a Chinese   D. a American(   ) 32. There are people in the photo.   A. nine   B. eight   C. seven   D. six(   ) 33. Beth's family name is .   A. Smith   B. White   C. Bush   D. Beth White(   ) 34. Leo and May's father is .   A. Mr White   B. Mr Smith   C. Mr Bush   D. Mr Read(   ) 35. Mrs White is May's         .   A. mother's friend   B. grandmother   C. mother's sister   D. father's sister