Which law can be used to calculate the number of moles of a co...

Question

Which law can be used to calculate the number of moles of a contained gas?

Accepted Answer

Hey there folks, welcome back or is it here, I'm going to be finding a true statement about a deal gasses in the container. Alright, so first one, the volume of the gas is zero. Leaders at zero degrees Celsius, constant pressure and at a fixed amount. Okay, so here we're looking at PV equals NRT. So we're saying that constant, we have constant pressure soapy here, Wisconsin, we can ignore that fixed amount, which means. And here number of moles of gas is the same and then r is the gas constant? It's a constant. Always. Right. So here we're just looking at volume and temperature. So if the temperature here is zero then the volume here is also zero, right? Because V equals to t and if temperature equals zero, then volume has to equal to zero. However, here we're given temperature in degrees Celsius. Now remember anytime we're dealing with ideal gas law equation, temperature is always in Calvin. Right? So it has to be zero Calvin. Right? It can be zero degrees Celsius because zero degrees Celsius actually going to be 273.15 Calvin. Right? Not zero Calvin. So this does not make sense. It is not going to equal to zero when it's degrees Celsius. If this said zero Calvin then yes, that would be true. So this is incorrect. Right? So the number of gas molecules decreases by 50%. So it halves when temperature changes from 400°C to 200°C at constant pressure and constant volume. So if you actually take a look at this. This does not make any sense. Right? So, it doesn't even matter what the temperature is. Number of gas molecules is not going to decrease. Right? So, this kind of looks like they might be talking about avocados law because avid gardeners losses that volume and and number of moles of gas are directly proportional. But here we're not really dealing with volume, they're telling us that the temperature is changing. Right? So, unless we're opening this container and we're letting some of the gas molecules escape or we're adding more gas molecules, the number of gas molecules is not going to change at all. So, this just doesn't make sense at all. Right. See So here we're saying volume of a gas decreases by 50% when the temperature decreases from 80 to 40°C as constant pressure and a fixed amount of gas. So, we're talking about the volume of gas being directly proportional to temperature rates. Where I can see volume is directly proportional to temperature. So, this we're talking about Charles law. But the statement again is a little bit tricky because it's using degrees Celsius. Okay. So if we said that the temperature have right, we we have the temperature then the volume would would decrease by the same ratio because they're directly proportional. Right? But here again, we're talking about ideal gas law and temperature has to be in Calvin's. Okay, So having the temperature or decreasing the temperature by half in Calvin's is not the same thing as decreasing the temperature um in Celsius. Right. So if we were to actually convert these into Calvin's, This would not be half of of Calvin. Right? It would not have decreased by 50%. So this would not be correct. It would be correct if these temperatures were in Calvin. Alright. So moving on to d the volume of a gas doubles when the pressure changes from two P two P at a constant temperature and a fixed amount of gas. So here we're saying that we're going to double the volume if pressure here decreases, so volume here is going to be adversely proportional to pressure. Right? So one increases the other one decreases and vice versa. So this is Will's law, remember, and this is actually correct. So, at constant temperature and of course, fixed amount of gas, fixed and constant end when we decreased pressure, volume was going to increase by the same amount. Right. So here we decreased the pressure or we have to do it. That means volume will double. Right, So d is the correct statement here, and he is not because we already found the correct one. Alright, folks, so that's it. I hope you're able to follow along and we'll see you later

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Which law can be used to calculate the number of moles of a contained gas?

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