问题 选择题

下列说法不正确的是(  )

A.同温同压下,3molC2H2(g)和1molC6H6(g)的密度相等

B.非金属氧化物不一定是酸性氧化物,但大多数金属氧化物为碱性氧化物

C.具有相同分子数的甲酸甲酯与乙酸的共价键数相等

D.SO2、H2O2、活性炭都能使品红溶液褪色,但原理不同

答案

A、根据n=

m
M
=
V
Vm
,可得ρ=
m
V
=
M
Vm
,在同温同压下Vm相同,则密度与气体的相对分子质量成正比,与气体的质量无关,故A错误;

B、非金属氧化物包括酸性氧化物和不成盐氧化物,金属氧化物大都是碱性氧化物,还有一些是过氧化物、两性氧化物和酸性氧化物,故B正确;

C、一个甲酸甲酯分子中含有4个C-H键、2个C-O键、1个C=O键,一个乙酸分子中含有3个C-H键、1个C-C键、1个C-O键、1个C=O键和1个O-H键,则具有相同分子数的甲酸甲酯与乙酸含有相同数量的共价键,故C正确;

D、SO2使品红褪色发生的是化合反应,H2O2使品红褪色是由于H2O2的强氧化性,活性炭使品红褪色是由于活性炭的吸附作用,三者原理不同,故D正确.

故选A.

阅读理解

第三部分:阅读理解(共20小题;每小题2分,满分40分)

   阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项。

        Hsieh.a never--say--die young man,has mastered the technique of painting hy holding

   the paintbrush in his mouth.When he was sixteen,Hsieh had a terrible electrical accident.

   Both of his arms and the lower part of his right leg were cut off.He also lost sight in his

   rigllt eye.But Hsieh didn’t lose heart.He decided to learn art,and took the first difficult

    step toward changing his life.

        “At first.I tried to hoht a pen in my mouth.But I couldn’t control it,”Hsieh said,“Fi—nally,after trying over and over again,I learned tO write my OWn name.”

Learning to paint was even more difficuh.At first,every brushstroke he made caused

deep cuts in his mouth.It was ext remely painful.But Hsieh didn’t let the pain discourage

    him.“lnstead,I held the painlbrusb even tighter,”Hsieh explained in a firm voice.“l   

knew if I gave up.it would not only be the end of my painting,hut also the end of my

struggle for a better life.”No matter what the obstacle(障碍)is,Hsieh always manages to

find the bright side of the situation.

  Hsieh works hard tO inspire others.He is a tireless lecturer,giving about four hundred

formal speeches a year!“If a person like me can lead a happy life,”Hsieh explained,“why

would regular people feel unhappy?It doesn’t always take tWO arms tO achieve your dreams.

A11 it lakes is a warm heart.”

56.What happened tO Hsieh when he was young?

    A.He was struck by electricity.

    B.His left leg was hurt.

    C.He lost heart because of failure.

    D.He was ill for two months.

57.Which of the following is his character?

  A.Realistic thought.    B.Impressive works.

  C.Unexpected news.    D.Belief in SUCCESS.

58.Which is right?

    A.Hsieh once got the help from the government.

    B.Only such a person like Hsieh can succeed.

    C.He touched himself before he began to paint.

    D.It doesn’t always take tWO arms to realize one’S dream.

59.Which is the best title of the passage?

  A.How to learn painting.    B.A painter without hands.

  C.A man who was hurt.     D.How to make oneself well—known.

单项选择题