问题 选择题

在大量的硫酸铜饱和溶液中,其他条件不变,再加入16克无水硫酸铜,下列说法正确的是

A.溶液仍然饱和,但浓度变大

B.析出晶体的质量大于25克

C.析出晶体的质量等于25克

D.析出晶体的质量大于16克、小于25克

答案

答案:B

题目分析:硫酸铜溶液已经达到饱和状态,所以再加入16克无水硫酸铜,不能再溶解,必然析出晶体。由于析出的晶体是CuSO4·5H2O,从而导致原溶液中溶剂减少,因此实际析出的晶体质量大于25g,答案选B。

点评:该题是中等难度的试题,也是高考中的常见题型。试题综合性强,侧重对学生能力的培养。该题的关键是明确硫酸铜再溶液中中析出时,会带结晶水,然后结合题意计算即可。

阅读理解

阅读理解

       BEIJING, June 11(Xinhua)一The Red Cross Society of China(RCSC)is planning to spend 2. 5 billion yuan (362. 32 million U. S. dollars)on reconstruction projects(重建工程)in areas hit by the May 12

earthquake.   

       The money would be the first part to go to reconstruction in quake areas from the donations the

RCSC had received so far, the organization said in a statement(声明)here on Wednesday. About 1. 8

billion yuan would go to the worst hit southwestern Sichuan Province, 460 million yuan to northwestern

Gansu Province and 240 million to Shaanxi Province.

       The funds would be spent in building hospitals,schools,houses and quake prevention facilities

(防震设施).

       The RCSC would first think of lonely areas and people in need,including orphans(孤儿), the

disabled and elderly who lost family members,the statement said.

       So far,the RCSC had received 4. 12 billion yuan of donations and 900 million yuan had been spent

in helping people hit by the earthquake.

       The rest of the donations would go to reconstruction projects,the statement said.

1. How much donation has the RCSC received so far?

A. 2. 5 billion yuan      

B. 240 million yuan

C. 4. 12 billion yuan    

D. 900 million yuan

2. For the reconstruction projects,how much would go to Sichuan Province?

A. 1. 8 billion yuan      

B. 460 million yuan

C. 240 million yuan      

D. 2. 5 billion yuan

3. Which province was the most seriously hit the May 12 earthquake?       

A. Gansu    

B. Jiangsu    

C. Sichuan  

D. Shaanxi

4. The money would first be spent to help_______.

A. orphans,homeless people and the disabled

B. any people in need

C. children and the elderly

D. we don't know  

多项选择题