题干

可逆反应2SO2(g)+O2(g)2SO3(g) ΔH<0在一定条件下达到平衡状态,时间为t1时改变条件。化学反应速率与反应时间关系如图。下列说法中正确的是

A:维持温度、反应体系体积不变,t1时充入SO3(g)

B:维持压强不变,t1时升高反应体系温度

C:维持温度不变,t1时扩大反应体系体积

D:维持温度、压强不变,t1时充入SO3(g)

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D

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       What is the best-selling book in the world? Is it the Harry Potter series or Secret Garden? According to the Guinness World Records, the Xinhua Dictionary, published by the Commercial Press in China, is the world’s most popular dictionary and the best-selling book.

       In 1950, Chinese language experts(专家) and scholars, Wei Jiangong and Ye Shengtao, started to edit(编辑) the Xinhua Dictionary. There was a lot of discussion, research and paper work. Some hand scripts (稿件) were checked again and again like compositions, People's Daily reported. Many people's hard work and interesting stories went into making the dictionary.

        In 1953, the first Xinhua Dictionary was published. Today, 567 million copies of the dictionary have been sold worldwide

      However, revisions (修订) to the dictionary continue to be made. According to Yu Guilin from Commercial Press, editors(编辑) usually summarize (总结) the meaning of words again while revising. If the example sentences are out of date, editors need to have experiences and make new examples. “To give a correct explanation of the word ‘焗油 (deep condition)’ , one editor went to a barber shop (理发店) to experience it for himself,” Yu told the Beijing Times. So far, the Xinhua Dictionary has been revised 11 times.

     To keep up with the times, some popular and widely used internet words are also added to the dictionary. For example, in the 11th edition, the phrases “晒工资 (show off salary)” and “晒照片 (show off pictures)” were included.

       All these efforts create the “National Dictionary” of China. The Xinhua Dictionary is not only a useful tool for generations of Chinese people. It also helps foreigners who are learning the Chinese language and culture.