题干

对Na2O2与CO2和H2O(g)混合气体的反应来说,下列说法错误的是(  )

A:只要参加反应的Na2O2一定,反应生成的氧气就一定

B:只要CO2和H2O(g)的总的物质的量一定,反应所消耗的Na2O2的量就一定

C:只要气体的总物质的量一定,反应中所转移的电子的物质的量就一定

D:只要混合气体的总物质的量一定,固体所增加的质量就一定

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D

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    If English means endless new words, difficult grammar and sometimes strange pronunciation, you are wrong. Haven't you noticed that you have become smarter since you started to learn a language?

    According to a new study by a British university, learning a second language can lead to an increase in your brain power. Researchers found that learning other languages changes grey mater. This is the area of the brain which processes information. It is similar to the way that exercise builds muscles.

    The study also found the effect is greater when the younger people learn a second language. A team led by Dr. Andrea Mechelli, from University College London, took a group of Britons who only spoke English. They were compared with a group of bilinguals who had learnt a second language before the age of five, as well as a number of later learners.

    Scans showed that grey mater density(密度) in the brain was greater in bilinguals than in people without a second language.

    “Our findings suggest that the structure of the brain is changed by the experience of learning a second language,” said the scientists. It means that the change itself increases the ability to learn.

    Professor Dylan Vaughan Jones of the University of Wales, has researched the link between bilingualism and maths skills. “Having two languages gives you two windows on the world and makes the brain more flexible,” he said. “You are actually going beyond language and have a better understanding of different ideas.”

    The findings were matched in a study of native Italian speakers who had learned English as a second language between the ages of two and thirty-four. Reading, writing, and comprehension were all tested. The results showed that the younger they started to learn, the better. “Studying a language means you get an entrance to another world,” explained the scientists.