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问题 选择题

某金属的氯化物溶液150g，溶质质量分数为3.9%，向其中滴加AgNO3溶液直至不再产生氯化银沉淀为止，过滤干燥得到固体14.35g．该金属氯化物的化学式为（　　）

A．NaCl

B．MgCl2

C．CaCl2

D．FeCl3

答案

该金属氯化物的质量=150g×3.9%=5.85g

该金属氯化物中氯元素的质量=14.35g×

35.5
143.5
×100%=3.55g

该金属氯化物中金属元素与氯元素的质量比=（5.85g-3.55g）：3.55g=230：355

A、NaCl中金属元素钠与氯元素的质量比=23：35.5=230：355，故A正确；

B、MgCl2中金属元素镁与氯元素的质量比=24：（35.5×2）=24：73≠230：355，故B不正确；

C、CaCl2中金属元素钙与氯元素的质量比=40：（35.5×2）=40：73≠230：355，故C不正确；

D、FeCl3中金属元素铁与氯元素的质量比=56：（35.5×3）=560：1065≠230：355，故D不正确；

故选A．

问答题

简述内质网的形态类型及各自功能特点。
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单项选择题

Deflation is an economic theory relating changes in the price levels to changes in the quantity of money. In its developed (1) , it constitutes an analysis of the (2) underlying inflation and deflation. As (3) by the English philosopher John Locke in the 17th century, the Scottish (4) David Hume in the 18th century, and (5) , it was a weapon (6) the mercantilists, who were thought to equate wealth with money. If the (7) of money by a nation merely raised (8) , argued the quantity theorists, then a "favourable" balance of trade, (9) desired by mercantilists, would increase the supply of money but would not in-crease (10) . In the 19th century the quantity theory (11) to the ascendancy of free trade over protectionism. In the 19th and 20th centuries it played a part in the (12) of business cycles and in the theory of foreign (13) rates.

The (14) theory came under attack during the 1930s, (15) monetary expansion seemed ineffective in combating deflation. Economists argued that the levels of investment and government spending were more important than the money supply in determining economic activity.

The tide of opinion (16) again in the 1960s, when experience (17) post-World WarⅡ inflation and new empirical (18) of money and prices— (19) A Monetary History of the United States (1963) by Milton Friedman and Anna Schwartz—restored much of the quantity theory’ s lost prestige. One implication of this theory is that the size of the stock of money must be considered when shaping governmental policies (20) to control prices and maintain full employment.

18（）

A.studies

B.discovers

C.findings

D.questions
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