Oxygen is a/an ___. A. element B. compound C. mixture D. solution 相关知识点: 试题来源: 解析 A。氧是一种元素。选项 A“element”是元素,氧是元素;选项 B“compound”是化合物;选项 C“mixture”是混合物;选项 D“solution”是溶液。反馈...
The atmosphere is a mixture of , including oxygen, water vapor, etc. (gas) 相关知识点: 试题来源: 解析 1.gases 【解答过程】句意:大气是气体的混合物,包括氧气,水蒸气等等。根据“including oxygen, water vapor, etc.”可知此处指不同的气体种类。故填gases。
Air is a mixture of different gases. What is the main component of air? A. Oxygen. B. Nitrogen. C. Carbon dioxide. D. Hydrogen. 相关知识点: 试题来源: 解析 B。解析:空气的主要成分是氮气。选项 A 氧气不是主要成分;选项 C 二氧化碳含量很少;选项 D 氢气不是空气的主要成分。
本题考查定语从句,先行词是air。,本句可分为两个单句: Air is a mixture of gases(空气一种气体混合物),和 Oxygen forms 21% by volume of air(氧气按体积占空气的21%),of表示范围,which代指ai,rin 表示地点或时间,to表示方向,by表示方式,所以答案是D ...
Air is a mixture of gases. Which gas is essential for combustion? A. Oxygen. B. Nitrogen. C. Carbon dioxide. D. Hydrogen. 相关知识点: 试题来源: 解析 A。氧气是燃烧必需的气体。B 选项氮气不是燃烧必需的;C 选项二氧化碳不是燃烧必需的;D 选项氢气不是空气中主要成分也不是燃烧必需来自空气。
aAir is a mixture of gases, consists mainly of nitrogen and oxygen, by volume, about 78% of the nitrogen in the air, oxygen and inert gas accounted for 21%, accounted for 0.94, accounting for about 0.03 of the carbon dioxide, water vapor and impurity accounted for about 0.03 of the. ...
Further, oxygen leakage is minimized by connecting the modular oxygen-providing assembly at a point of the respiration circuit of the greater respiration apparatus that is downstream from a valving arrangement normally used for venting patient exhaust flow and for controlling system pressure by venting ...
The air we breathe in is actually a mof different gases, such as oxygen, hydrogen and so on. 相关知识点: 试题来源: 解析 1.mixture 考查名词。句意:我们吸入的空气实际上是不同气体的混合物,如氧、氢等。根据句意和首字母可知此处是名词mixture "混合物" ,由a修饰,故填mixture。
9Air is a mixture of various gases. The main gases are oxygen and nitrogen.The other gases are carbon dioxide,water vapour and a number of rare gases. Nitrogen occupies 78% and the other gases including carbon dioxide,water vapour and a number of rare gases occupy 1% of the total volume...
The air we breathe in is actually a m___ of different gases, such as oxygen, hydrogen and so on. 答案 答案:mixture.mixture表示"混合物",不定冠词a后接单数可数名词.故填mixture.我们吸入的空气实际上是不同气体的混合物,比如氧气,氢气等.相关推荐 1The air we breathe in is actually a m___ ...