### chemistry question!

So here we are, in the middle of nowhere, and Mycah has come across a question in her chemistry class that we are perplexed by.

Q: If you increase the temperature of a volume of air by four times while at the same time doubling the pressure, would the volume of air increase or decrease? Why? Text us at +881623458586 on our satellite system.

April 30, 2017 at 3:46 pm

PV/NRT, That is what I remember from college. Pressure x Volume / (moles x gas constant x temp). If your looking for the change, then P1 x V1 / (N1 x R x T1) = P2 x V2 / (N2 x R x T2). Plug in the knowns and solve for the unknown. 4 x T1 = T2 (T2 is 4 x greater than T1), If you double the volume, then 2 x V1 = V2. Hope that helps! I’ll try texting too.

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April 30, 2017 at 9:32 pm

Hope your sails are full of favorable winds and seas are kind. The equation you need to use is PV=nRT

P is pressure, V is volume, n is number of moles, R is a gas constant, T is temperature. Now we know that the temp increases by a factor of 4 and pressure increases by a factor of 2. There is a direct relationship between temperature and volume meaning that when temp increases by a factor of 4, volume increases by a factor of 4 as well. Pressure and volume have an inverse relationship so when pressure increases by a factor of 2, volume will decrease by a factor of 2. However an increase by a factor of 4 (bc of temp) will over power the decrease by a factor of 2 (bc of pressure) will lead to an overall increase in volume.

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May 1, 2017 at 3:57 am

Reblogged this on karlmollermission and commented:

Boyle’s Law tells us that. PV=nRT. n is the number of moles, basically the amount of gas. P is the pressure. V is the volume. R is a constant (8.31, if I remember correctly). And T is the temperature. So in your case, the right side of that equation will increase by a factor of four (temperature), so to retain equality the left side must also increase by a factor of four. The doubling of pressure will contribute a factor of two, so three is another factor of two that must appear on the left. That can occur only in the remaining variable, the volume. Thus the volume will increase by a factor of two, or in plain language, it will double. This all assumes a sealed container.

I hope this was helpful, Love the Moller’s in NZ. (Terri & Conrad)

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