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Estimate the total number of air molecul...

Estimate the total number of air molecules (inclusive of oxygen, nitrogen, water vapour and other constituents) in a room of capacity `25.0 m^3` at a temperature of `27 ^@C` and 1 atm pressure.

Text Solution

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We are given:
`p=1atm =1.01 times 10^5 Pa`
`V=25 m^3`
`T=27^@C=300K`
`R=8.31J//mol//k`
We are to calculate , number of molecules , N
Using the relations :
`pV=mu RT`
`mu=(pV)/(RT)=(1.01 times 10^5 times 25)/(8.31 times 300)=1.013 times 10^3` moles
Now, one mole of a gas contains =`6.023 times 10^23` molecules
`therefore 1.023 times 10^3` moles would contain
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