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问题 选择题

早晨，小草上挂着晶莹的露珠，露珠的形成属于物态变化中的

A．熔化

B．汽化

C．液化

D．凝华

答案

答案：C

露珠是液态，只有水蒸气液化才可形成，而汽化的末状态是气态，显然不是，熔化的末状态虽然是液态，但初状态是固态，故不符合题意；凝华的末态是固态，也不符合题意；

故选C

计算题

“温室效应”是全球关注的环境问题之一。CO2是目前大气中含量最高的一种温室气体。因此，控制和治理CO2是解决温室效应的有效途径。

（1）将不同量的CO(g)和H2O(g)分别通入到体积为2L的恒容密闭容器中，进行反应CO(g)+H2O(g)CO2(g)+H2(g)，得到如下三组数据：

实验组温度/℃起始量/mol平衡量/mol达到平衡所需时间/min
COH2OH2CO
1650421.62.46
2900210.41.63
3900abcdt
 

① 实验1条件下平衡常数K=     （保留小数点后二位数字）。

② 实验3中，若平衡时，CO的转化率大于水蒸气，则a/b 的值    （填具体值或取值范围）。

③ 实验4，若900℃时，在此容器中加入10molCO、5molH2O、2molCO2、5molH2，则此时v(正)     v(逆)（填“<”、“>”、“=”）。

（2）CO2在自然界循环时可与CaCO3反应，CaCO3是一种难溶物质，其Ksp=2.8×10—9。CaCl2溶液与Na2CO3溶液混合可形成CaCO3沉淀，现将等体积的CaCl2溶液与Na2CO3溶液混合，若Na2CO3溶液的浓度为2×10—4mo1/L，则生成沉淀所需CaCl2溶液的最小浓度为   。

（3）已知BaSO4(s) + 4C(s) ="4CO(g)" + BaS(s)  △H1 =+571.2kJ/mol，

BaSO4(s) + 2C(s) = 2CO2(g) + BaS(s)  △H2="+226.2" kJ/mol。

则反应C(s) + CO2(g) = 2CO(g)的△H3=      kJ/mol。

（4）寻找新能源是解决温室效应的一条重要思路。磷酸亚铁锂LiFePO4是一种新型汽车锂离子电池，总反应为：FePO4+Li        LiFePO4，电池中的固体电解质可传导Li+，则该电池放电时的正极和负极反应式分别为：                和                 。若用该电池电解蒸馏水（电解池电极均为惰性电极），当电解池两极共有3360mL气体（标准状况）产生时，该电池消耗锂的质量为       。(Li的相对原子质量约为7.0)
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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.

19（）

A.similar to

B. such as

C.along with

D.aside from
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