问题 选择题

下列物质属于氧化物的是(  )

A.氯化钠

B.过氧化氢溶液

C.碳酸钙(CaCO3

D.水

答案

A、氯化钠,由钠和氯元素组成,虽由两种元素组成,但却不含氧元素,故不属于氧化物;

B、过氧化氢溶液,过氧化氢由氢、氧两种元素组成又含有氧元素,属于氧化物,但溶液却是混合物,因此过氧化氢溶液不属于氧化物;

C、碳酸钙,由钙、碳、氧三种元素组成,虽含氧但却不属于氧化物;

D、水,由氢、氧两种元素组成且含氧元素的化合物,属于氧化物.

故选D

改错题

短文改错(共10小题,每小题1.5分,满分15分)

此题要求改正所给短文中的错误.对标题号的每一行做出判断:如无错误,在该行右边的横线上划(√);如有错误(每行只有一个错误),则按下列情况改正:

此行多一个词:把多余的词用斜线划掉,在该行右边横线上写出该词,并也用斜线划掉。

此行缺一个词:在缺词处加一个漏字符号(^),在该行右边横线上写出该加的词。

此行错一个词:在错的词下划一横线,在该行右边横线上写出改正后的词。

注意:原行没有错的不要改。I still remember how nervous I am on my first day in the new school  

小题1:      

three years ago, while I found it difficult to follow my teacher in the first小题2:     

English class. The teacher spoke English throughout the class, that was

小题3:     

totally different from the lessons I had before.                   

小题4:     

In the morning class the next day, the English teacher came to me  小题5:     

while I was reading the text loud as other students. After Listening to 小题6:     

her for a while, she gave me a big smile and said the liked my voice   小题7:     

very much. The smile shone on the whole day and the following day. A

小题8:     

week later on, I volunteered to take charge of the English study in my class.小题9:     

Thanks to the comforted smile, I began to be confident since them.

小题10:    

多项选择题