Versus looking at, for example, helium or neon or argon, these are all inert gases, inert meaning essentially do not react, those were grouped together in the periodic table.

相反，他发现氦，氖，氩，都是惰性气体，惰性的意思是基本不参与化学反应，因此把它们放在周期表中的同一类里。

麻省理工公开课 - 化学原理课程节选

How many moles of gas are there in each case, in reactants and products? If that changes, of course you know that the pressure in there is going to change at constant volume if the amount of gas in there is changing.

在反应物和生成物中，各有多少摩尔的气体？,如果它发生了变化,当然在等体条件下，如果气体的总量,发生了变化，压强也会发生变化。

麻省理工公开课 - 热力学与动力学课程节选

And, this is a really clever reaction because titanium tetrachloride is a gas.

这是一个非常巧妙的反应,因为四氯化钛是一种气体。

麻省理工公开课 - 固态化学导论课程节选