Pure compounds and elements differ from mixtures in one key way: the substances in a pure compound are held together by chemical bonds. These chemical bonds cannot be broken. Since they contain a single substance only, elements cannot be decomposed by ordinary chemical methods, such as the appli...
aA compound is a substance that can be split into two or more elements. Water is a compound because it can be split into its components, hydrogen and oxygen. 化合物是可以被分裂成两个或多个元素的物质。 因为它可以被分裂成它的组分、氢和氧气,水是化合物。[translate]...
A. material B. substance C. agent D. element 相关知识点: 试题来源: 解析 D 正确答案:D 解析:element n.(化学)元素;成分,要素material n.材料,原料;素材,资料。substance n.物质;实质;要旨,基本内容;根据,理由。agent n.代理人,代理商;(化学)剂。反馈...
三、阅读理解 A useful definition of an air pollutant is a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or material adversely(有害地). Air pollution requires a very flexible definition that permits continuous change....
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Chemistry - SOLUTIONS 1) Suppose you are given a substance consisting of 3 elements. (a) Can you conclude that the substance is a compound? EXPLAIN younits) •
Scientists figured out a way to name every element they discovered so they won't have any issues when combining elements to form any kind of compound because there an infinite amounts of chemical compounds. We need a systematic method for naming compounds because the scientists often use chemical...
解析 CA compound is made up of 2 or more elements chemically combined. It has different properties from the elements it is made of. It is a pure substance with fixed melting and boiling points. It can only be separated by chemical means. ...
A substance that cannot be broken down into simpler substances by chemical means is called a(n) ___. A. element B. compound C. mixture D. solution 相关知识点: 试题来源: 解析 A。本题考查化学物质的分类。选项 B“compound”是化合物,可以通过化学方法分解为更简单的物质;选项 C“mixture”是混...
Why is ammonia a compound? Compounds: There are 118 known chemical elements, which are substances that cannot be further simplified using chemistry. When two or more of these elements are bonded together to form a new substance, that new substance is called a chemical compound. ...