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问题 填空题

（7分）“阿波罗号飞船”所用的氢氧燃料电池的电极应为：负极：2H2＋4OH－－4e－＝4H2O，则正极反应为                              ；该电池工作时,通氢气的一极发生                      反应（填氧化、还原），每转移4摩电子,电池内增加         摩水，负极附近溶液的PH值                ，（填升高、降低、不变），正极附近  [H+]    （填升高、降低、不变）

答案

（7分）

正极反应为O2＋2H2O＋4e－＝4OH－（2分），还原（1分），2（2分），降低（1分）降低（1分）

解答题
已知tan（α-β）=
1
2
，tanβ=-
1
7
，求tan（2α-β）的值．
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单项选择题

THE QUEEN ANNE HOUSE　　The house style that dominated American housing during the 1880s and 1890s was known as Queen Anne, a curious name for an American style. The name was, in fact, a historical accident, originating with fashionable architects in Victorian England who coined it with apparently no reason other than its pleasing sound. The Queen Anne style was loosely based on medieval structures built long before 1702, the beginning year of Queen Anne’s reign.　　A distinctive characteristic found in most Queen Anne houses is the unusual roof shape --- a steeply pitched, hipped central portion with protruding lower front and side extensions that end in gables. It is often possible to spot these distinctive roof forms from several blocks away. Another feature of this style is the detailing, shown in the wood shingle siding cut into fanciful decorative patterns of scallops, curves, diamonds, or triangles. Queen Anne houses are almost always asymmetrical. If you draw an imaginary line down the middle of one, you will see how drastically different the right and left sides are, all the way from ground level to roof peak. A final characteristic is the inviting wraparound porch that includes the front door area and then extends around to either the right or left side of the house.　　Queen Anne houses faded from fashion early in the twentieth century as the public’s taste shifted toward the more modern Prairie and Craftsman style houses. Today, however, Queen Anne houses are favorite symbols of the past, painstakingly and lovingly restored by old-house buffs and reproduced by builders who give faithful attention to the distinctive shapes and detailing that were first popularized more than one hundred years ago.

The word it in paragraph 1 refers to

A．style

B．name

C．accident

D．England
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