Learn about Junior Chemistry, Gases 1, in this comprehensive video by bannanaiscool.
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Male Speaker: We live in a country so we don't have those nice kinds of things that people in city do like water that just turns on the tap and it's already nicely pressurized, we got to do that in our own houses, so this is a pressure tank so there is a bladder inside of this tank that's filled with air, and that air exerts a pressure on to the water which drives it through out the pluming in the house. Hey pressure is something that's very important, gases which are really just solutions of different, molecules in the air, very, very important to us in many different ways from, air bladder here to tires that we drive on in our bikes and in our cars hey lets talk about pressure in gases. Gas comes from the Greek word khaos, and that's appropriate because gases are the most khaotic disorganized randomized type of matter that we actually have, now in order to understand gases we need to know something about how we measure them, now because it compressible we actually can exert pressure on gases and they will respond by actually changing their pressure and so gases have pressures that we can measure lots of different ways in doing that, pounds per square range we something that we used for a lot of years before metric to go, and so now here are some really common pressure units that you need to know about. Atmospheres torres and kilo pascals, kilo pascals mostly use all over the world, atmospheres a lot in American chemistry and torres was a traditional one that we used for gases, gases are compressible they occupy their container volume fully because they undergo defusion those are properties of gases, now in terms of the numbers here, the torre was the original one that was given by Torre Shelly he was Italiano Torre Shelly he come up with a number several hundred and sixty torre, 760 torre which actually gives 760 millimeters of mercury or how much mercury rises at sea level in a glass two that's incompletely evacuated with from air molecules, mercury arise up in the counts 760 millimeters, now we call it torre, in order of Torre Shelly what is that this is a very big number what we just call it one atmosphere and that's exactly the most convenient way of describing pressure in atmospheres, but you want to see that necessarily if you work it in Canada specially here. So what is the Equivalence between one atmosphere and 760 torre in terms of KPa or Kilo Pascals, which is force per unit area, newtons per meter, that's really what kilo pascal is all and what really pressure gives, it's a force per unit area, well the number is 101.325, 101.325, sorry about that but that's what it is, and that's one we use in the majority of calculations coming up.