问题 选择题

善于梳理化学知识,能使你头脑更聪明。以下正确的一组(     )

A 化学与能源B 微粒观点解释现象
乙醇和汽油都是可再生能源,应大力推广

发展火力发电以解决电力紧张

花香四溢—分子在不断运动

热胀冷缩—分子大小发生变化

C 化学与人体健康 D 化学与应用
多吃水果有利于补充维生素

用工业盐(亚硝酸钠)腌渍蔬菜

用洗涤剂除去油污—乳化作用

进入未开发的溶洞探险—用火把照明

 

答案

答案:D

题目分析:根据已有化学知识分析。

A、汽油是化石燃料,是一种不可再生的能源,错误;

B、热胀冷缩是因为分子间的间隔随温度的变化而变化导致的,而分子本身大小没有发生变化,错误;

C、工业盐中的亚硝酸钠有毒,如用其腌渍蔬菜,会对人体健康造成损害,错误;

D、洗涤剂中含有乳化剂,能对油污起乳化作用,故用洗涤剂能除去油污;未开发的溶洞中可能会含有大量的二氧化碳气体,而二氧化碳不能供给呼吸,故若贸然进入,会使人窒息甚至死亡,且由于二氧化碳不支持燃烧,所以进入未开发的溶洞探险,可用火把照明,若火把熄灭,则说明二氧化碳含量过高,要立即退出,正确。故选D

点评:本题难度不大,但考查的知识点较多,熟记相关基础知识是解题的关键,此外,具体解答时,可采用排除法,会更便捷些。

判断题
阅读理解

Healthy eating habits are one of the most important lessons a child learns. Parents can make a plan of action for each child’s nutritional needs.

Creating healthy habits

Breakfast is necessary to provide the nutrition and energy for an active day. Studies show that children do better in school when they begin the day with breakfast.

Include your child as much as possible in meal planning and preparation. He is more likely to eat food that he has helped put on the table. Cooking at home and at school encourages curiosity and motivation to try new foods.

The mealtime enviroment has a lot to do with how your child will feel about food. Try to keep the time and location of your meals consistent. Keep the meal itself as the main event by reserving the use of toys, telephone calls and television for later.

Help them regard food such as fruit as being important every day, and other food such as chips as being an occasional treat. Prepare food in a variety of ways.

Snacks

Snacks provide necessary energy for children between meals. Be sure to have plenty of healthy snack choices such as fruit and yogurt available at these times. Snacks should not replace a meal but provide a valuable supplement.

小题1:The passage is written mainly to        

A.teach children to develop good eating habits.

B.exchange ideas with experienced parents

C.learn about children’s food preferrences

D.offer parents some useful suggestions小题2:A child is more likely to try new foods      

A.when he spends time with other children

B.if he helps prepare the food himself

C.after he has had an active day

D.when he has no snacks小题3:The underlined word “reserving” most probably means        

A.putting into

B.calling for

C.talking about

D.setting aside小题4:What would be the best title for the passage?

A.You are what you eat

B.Cook dinner for your child

C.Healthy eating for kids

D.Pleasure in everyday meals