问题 填空题

①煤油燃烧,②氯化氢气体和氨气混合,产生______,在碘化钾溶液中加入硝酸银溶液,产生______(以上空格填所产生的现象),以上三种物质的变化,都是______变化.在这些变化中,常伴随发生______、______、______、______、______等现象,还伴随着______的吸收或释放,如石蜡、酒精燃烧时,有______和______放出,干电池放电时内部物质发生可化学变化,释放出______,绿色植物则需要______才能进行光合作用等.

答案

氯化氢气体和氨气混合,产生白烟,在碘化钾溶液中加入硝酸银溶液,产生黄色沉淀,以上三种物质的变化,都是化学变化.在这些变化中,常伴随发生放热、发光、变色、放出气体、生成沉淀等现象,还伴随着能量的吸收或释放,如石蜡、酒精燃烧时,有热量和光放出,干电池放电时内部物质发生可化学变化,释放出电能,绿色植物则需要吸收太阳光能进行光合作用等

故答案为:白烟;黄色沉淀;化学;放热、发光、变色、放出气体、生成沉淀;能量;热量和光;电能;吸收太阳能

单项选择题
阅读理解

Every day, life is made and lost. Every day, life goes on. Every day we experience some of the most important parts of life and may not even realize it: love, generosity, and perseverance. These values aren’t just important to us; they make the world what it is.

Scientists say that gravitaional(重力的)force makes the world turn, but some people say that love makes it go round. Love can be found anywhere: in families, friends, even complete strangers. Even if you can’t see it, you know it’s there.

Love may connect people all over the world, but what would the world be without generosity? Whether after a national disaster, or a school fund-raiser, one thing is certain----it is better to give than to receive. Generosity is found everywhere and whether it’s a large or small act, it makes a difference. Sometimes, though, it takes effort to be generous, which leads us to perseverance.

Founding a country, riding a bike, or finishing an essay, these are all finished with perseverance. Perseverance is the one thing that can help us achieve whatever we want. It is what helps scientists to discover cures for diseases, and athletes to become champions.

There is an infinite(无穷的) number of things we value, but without love, generosity and perseverance, we just don’t think that our life or the world would be the way it is.

1. The underlined word “it” in the second paragraph refers to “________”.

A. the world              B. gravitational force

C. value                    D. experience

2. To be generous, the author thinks________.

A. you needn’t make efforts                    B. you should be qualified

C. you should give all you have        D. you will find it good to give

3. Which of the following statements is TRUE according to the passage?

A. Perseverance is the only thing that can halp us to achieve success.

B. People don’t understand the life they are experiencing at all.

C. We can find love in complete strangers sometimes.

D. What the world is like depends on gravity and love.

4. What would be the best title for the passage?

A. Success and Failure                    B. Three Values

C. Endless Love                          D. Life Full of Hope