Dalton wondered why the heavier and lighter gases in the atmosphere did not separate as oil and water do. He finally concluded t

admin2010-01-13  39

问题    Dalton wondered why the heavier and lighter gases in the atmosphere did not separate as oil and water do. He finally concluded that the constituent 【C1】______ must exist in the form of tiny particles or atoms and that these  【C2】______  be completely mixed together in the atmosphere. This threw a new light in 【C3】______  law of definite proportions. It was only necessary to suppose that the atoms 【C4】______  combine into small groups of uniform  【C5】______  and so form more complex substance;  【C6】______  the mystery of this law was  【C7】______ . Dalton suggested, for example, that carbon monoxide 【C8】______  formed by the one with one  【C9】______  of atoms of carbon and oxygen, 【C10】______  carbon dioxide results from a single 【C11】______  of carbon uniting with two atoms of oxygen. Assuming this to be true,  【C12】______  the definite proportions of Prout’s law 【C13】______  all chemical compounds the different constituents 【C14】______  enter in unvarying proportions would naturally 【C15】______  the relative weights of the many different kinds of atoms.
【C2】______

选项 A、ought
B、could
C、will
D、must

答案D

解析  情态动词must在这里是“必定、必须”的意思。
转载请注明原文地址:https://kaotiyun.com/show/Vumi777K
0

最新回复(0)