问题 问答题

硝酸铵受撞击或受热后会发生爆炸性的分解,可用作炸药.又因其含氮量较高,也用作化肥.请计算:

(1)100g硝酸铵中含氮元素的质量.______

(2)多少克硫酸铵中的氮元素与100g硝酸铵中氮元素的质量相等?______.

答案

(1)根据物质中某元素的质量=该物质×物质中某元素的质量分数,可得100g硝酸铵中含氮元素的质量为:

100g×

14×2
80
×100%=35g;

(2)设x克硫酸铵中的氮元素与100g硝酸铵中氮元素的质量相当,可得

 x×

14×2
132
×100%=100g×
14×2
80
×100%     x=165g

故答案为:35g;165g.

阅读理解

My tears run down from my cheeks (面颊) when I talk to my parents on the phone. What are they doing when I call them? Dad works from seven o’clock in the morning to nine o’clock in the evening. My mum does all the housework, she also has to work in the field. But I can’t do anything for them.

Every day she gets up at around 4 o’clock in the morning. When I sometimes call her at 7:30 in the evening, she tells me that she is still in the field and doesn’t have supper. I tell her I’ll study hard in the school. I also ask her to take care of herself and dad because I can’t live without them.

Mum says that the happiest time for dad and her is when my sister and I come back home.

We play cards in the room, watch TV, or do anything we like, with dad and mum making delicious food in the kitchen. It is also the happiest time for me.

Love, sometimes, doesn’t need many words. Love your parents like they love you. Give them a call, tell them you miss them.

小题1:Why can’t the writer live without their parents?

A.Because her parents give her money.

B.Because her parents need her to take care of them.

C.Because she loves her parents and they love her very much.

D.Because they afford (提供) her education (教育).小题2:The happiest time for the writer’s mum and dad is____________.

A.she and her sister help them make delicious food in the kitchen

B.her sister and her coming back home

C.they play cards in the room

D.they work in the field together小题3: Which of the following is the best title?

A.Mum and Dad

B.I love you, Mum and Dad

C.My Family

D.I Love My Family

单项选择题 A1/A2型题