问题 填空题

已知在25℃的水溶液中,AgX、AgY、AgZ均难溶于水,且Ksp(AgX)=1.8×10-10,Ksp(AgY)=

1.0×10-12,Ksp(AgZ)=8.7×10-17

(1)根据以上信息,判断AgX、AgY、AgZ三者的溶解度(用被溶解的溶质的物质的量/1L溶液表示)

s(AgX)、s(AgY)、s(AgZ)的大小顺序为:_____________________;

(2)若向AgY的饱和溶液中加入少量的AgX固体,则c(Y-)__________(填“增大”、“减小”或“不变”)。

(3)在25℃时,若取0.188g的AgY(相对分子质量188)固体放入100mL水中(忽略溶液体积的变化),则溶液中Y-的物质的量浓度为________________;

(4)由上述Ksp判断,在上述(3)的体系中,能否实现AgY向AgZ的转化?________(填写“能”或“不能”),请简述其理由:______________________。

答案

(1)s(AgX)>s(AgY)>s(AgZ) 

(2)减小

(3)1.0×10-6mol·L-1

(4)能;Ksp(AgY)=1.0×10-12>Ksp(AgZ)= 8.7×10-17

单项选择题

In 1998 consumers could purchase virtually anything over the Internet. Books, compact discs, and even stocks were (1) from World Wide Websites that seemed to (2) almost daily a few years earlier, some people had predicted that consuners accustomed to shopping in stores would be (3) to buy things that they could not see or touch (4) . For a growing number of time-starved consumers, however, shopping from their home computer was proving to be a convenient (5) to driving to the store.

A research estimated that in 1998 US consumers could purchase $ 7.3 billion of goods over the Internet, double the 1997 total. Finding a bargain was getting easier, (6) the rise of online auctions and Websites that did comparison shopping on the Internet for the best (7) .

For all the consumer interest, (8) in eyberspaee was still a largely (9) business, however. Internet pioneer Amazon. eom, which began selling books in 1995 and later (10) into recorded music and videos, posted (11) of $ 153.7 million in the third quarter, up from $ 37.9 million in the same period of 1997. Overall, (12) , the company’ s loss widened to $ 45.2 million from $9.6 million, and analysts did not expect the company to turn a profit (13) 2001. (14) the great loss, Amazon. tom had a stock market value of many billions, reflecting investors’ (15) about the future of the industry.

Internet retailing appealed (16) investors because it provided an efficient means for reaching millions of consumers without having the cost of operating (17) stores with their armies of salespeople. Selling online carried its own risks, however, (18) so many companies competing tor consumers’ attention, price competition was (19) and profit (20) thin or nonexistent.

3()

A.preferable

B.enjoyable

C.reluctant

D.indifferent

单项选择题