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问题 选择题

KClO3和KCl的混合物中含KCla克，加热分解完全后，KCl的质量是2a克，则原混合物中KClO3和KCl的质量比约是（　　）

A．1：1

B．2：1

C．1.64：1

D．1.5：1

答案

根据题目信息可知，生成的氯化钾的质量=2a-a=a克，设参加反应的氯酸钾的质量为X．

2KClO3

MnO2
.
△
2KCl+3O2↑

245         149

X           a克

245
149
═
X
a克

得：X=

245a
149
克

∴原混合物中KClO3和KCl的质量比=

245a
149
：a═
245
149
═1.64：1．．

故选C．

单项选择题

用实物法编制施工图预算时，计算完工程量之后的编制内容是（）。

A．套人工、材料、机械台班预算定额消耗量

B．套预算定额单价

C．进行工料分析

D．计算各项费用
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单项选择题

When anyone opens a current account at a bank, he is lending the bank money. He may (1) the repayment of the money at any time, either (2) cash or by drawing a check in favor of another person. (3) , the banker customer relationship is that of debtor and creditor who is (4) depending on whether the customer’s account is (5) credit or is overdrawn. But, in (6) to that basically simple concept," the bank and its customer (7) a large number of obligations to one another. Many of these obligations can give (8) to problems and complications but a bank customer, unlike, say, a buyer of goods, cannot complain that the law is (9) against him.

The bank must (10) its customer’s instructions, and not those of anyone else. (11) , for example, a customer opens an account, he instructs the bank to debit his account only in (12) of checks drawn by himself. He gives the bank (13) of his signature, and there is a very firm rule that the bank has no right or (14) to pay out a customer’s money (15) a check on which its customer’s signature has been (16) . It makes no difference that the forgery may have been a very (17) one, the bank must recognize its customer’s signature. For this reason there is no (18) to the customer in the practice, (19) by banks, of printing the customer’s name on his checks. If this (20) forgery, it is the bank that will lose, not the customer.

4（）

A.which

B.what

C.how

D.that
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