题干

用“ ”和“ ”代表两种不同的单质分子,它们在一定条件下能发生化学反应,反应前后的微观示意图如图所示,下列说法正确的是(   )

A:该反应有两种生成物

B:每个生成物分子由3个原子构成

C:该反应是化合反应

D:参加反应的“”和“”分子的个数比是2:1

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答案(点此获取答案解析)

C

同类题5

The values of artistic works, according to cultural relativism(相对主义), are simply reflections of local social and economic conditions. Such a view, however, fails to explain the ability of some works of art to excite the human mind across cultures and through centuries.

              History has witnessed the endless productions of Shakespearean plays in every major language of the world. It is never rare to find that Mozart packs Japanese concert halls, as Japanese painter Hiroshige does Paris galleries, Unique works of this kind are different from today’s popular art, even if they began as works of popular art. They have set themselves apart in their timeless appeal and will probably be enjoyed for centuries into the future.

               In a 1757 essay, the philosopher David Hume argued that because“the general principles of taste are uniform(不变的) in human nature,”the value of some works of art might be essentially permanent. He observed that Homer was still admired after two thousand years. Works of this type, he believed, spoke to deep and unvarying features of human nature and could continue to exist over centuries.

               Now researchers are applying scientific methods to the study of the universality of art. For example, evolutionary psychology is being used by literary scholars to explain the long-lasting themes and plot devices in fiction. The structures of musical pieces are now open to experimental analysis as never before. Research findings seem to indicate that the creation by a great artist is as permanent an achievement as the discovery by a great scientist.