Wednesday, 24 April 2013

1.20 understand the term molar volume of a gas and use its values (24 dm3 and 24,000 cm3) at room temperature and pressure (rtp) in calculations.

At standard temperature and pressure, one mole of any gas will occupy 24000 cm3; also known as 24dm3.

A really good way to do calculations with this information is by using this triangle:

In a recent past paper I did this was one of the questions: calculate the amount, in moles, of carbon dioxide gas collected if you collect 144cm3.

The correct way to find this out is by doing 144 / 24000 which gives you 0.006 Mol

13 comments:

  1. The photo won't show :( What is the triangle?

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  3. Just did the same question on Jan 2013 2C !! :D

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  4. how do you use pressure in chemistry calculations? examples please?

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  5. Im guessing the triangle in the photo should represent:

    Volume (dm3/cm3)
    ------------------------------------------------
    Moles x Molar Volume (dm3/cm3)

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  6. http://www.chemistryrules.me.uk/middle/amount.htm#amount - bas calc mass

    go to the heading 'amount - molar volume of a gas' and the triangle is there :)

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  7. Equation is: moles= volume/24 N.B the volume must be in dm^3 so if the question gives you the volume in cm^3 then divide it by 1000

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