Moles and gas volumes

This is similar to amount of substance, however we are working with gases and gas volumes alone. This works effectively when the substance is held at RTP.

When the volume is in cm cubed the equation is:

n=V/24000       n=Moles
                         V=volume
                         As for the 24,000 just don't question it! If that's what they want, that's what they'll get!

As usual we will go through some examples step by step. However, one thing you do need to know is RTP meaning room temperature and pressure.

What amount, in mol, of gas molecules is in 72 cm cubed of any gas at RTP?

This is simply plugged in:

n=72/24,000= 0.0030 moles

Now lets try something a little more brain tingling:

What is the volume in, cm cubed, of 2.130 x 10 to the power of negative 3 mol of a gas at RTP?

Once again we plug in the info we posses into the formula:

2.130 x10 neg 3=V/24000

We now need to rearrange this to form:

V= 2.130 x 10 neg 3 x 24,000= 51.12 cm cubed

It's just applying what information you posses and plugging it into the formula effectively! Do this with your question and you're cooking with gas!

Till next tyme! :)

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