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问题 选择题

将一定质量的镁、铝合金（不含其他物质）与足量的稀硫酸充分反应后，生成0.2g氢气，原混合物的质量不可能是

A．1.2g

B． 2.0g

C．2.2g

D．1.9g

答案

答案：A

根据化学方程式可知，镁、铝与足量盐酸反应，生成0.2克氢气所需的质量为：

Mg+2HCL═MgCl2+H2↑，2Al+6HCL═2AlCl3+3H2↑

24             2    54             6

2.4g          0.2g   1.8g           0.2g      

所以混合物的质量和必须满足大于1.8g，小于2.4g。只有A不符合要求，故选答案A

故选B．

阅读理解

阅读选择正确答案。

     Bill, Jack and I are in the same class at Chongqing No.2 High School. We are good friends, but we are

from different countries (国家). Bill is from England. He likes Chinese noodles very much. Jack's favorite

food is hamburgers. They look like twin (双胞胎) brothers, but they are not. Jack is from Canada. I come

from China. I like Chongqing food very much. They like singing very much and I like playing soccer

a lot.

1. We are in _______ now.

A. Beijing

B. Chongqing

C. America

2. We are from _______ countries.

A. same

B. different

C. all

3. Jack like _______ very much.

A. Chinese noodles

B. eggs

C. hamburgers

4. Jack is Bill's _______.

A. friend

B. brother

C. teacher

5. My favorite sport is _______.

A. driving

B. singing

C. soccer

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单项选择题

患者男性，42岁，消瘦，右上腹痛，查体：肝剑突下4cm，质硬，边缘不整，有结节，可闻及血管杂音，该患者最可能的诊断是

A．肝炎

B．肝癌

C．脂肪肝

D．肝淤血

E．肝脓肿
查看答案