# chemistry calculation A level

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#1
how do I find out what gas this is?

gas with dnesity 1.333 x 10^-3 g cm^-3 (RTP)
0
2 years ago
#2
(Original post by A*my)
how do I find out what gas this is?

gas with dnesity 1.333 x 10^-3 g cm^-3 (RTP)
Rermember that all gases obey the gas laws (more or less).

Avogadro's law says that all gases occupy the same volume for the same number of moles (OWTTE)

Hence find out the mass of the gas molar volume under any conditions you know and you have the relative mass.
0
2 years ago
#3
You may know that a mole of any gas occupies 24 dm^3 at RTP.
You need to convert the units, but using this and the information given you can find the molecular mass, which will hopefully be easy to recognise as a common gas
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#4
ok thanks guys. Do I have to use the density = mass/vol formula

so 1.333x10^-3 = mass / 24000
when moles = 1
so mass = moles x Mr
so mass found = Mr
and you have found the Mr, which is Oxygen.

Or is there another way?
0
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