Volume Mixing Ratio Lab Report

Exercise 1

The abundance of nitrogen in the standard dry atmospheric composition is 781,000ppmv.
The mass mixing ratio is the volume mixing ratio multiplied by the molecular mass of nitrogen all divided by the molecular mass of air. As the molecular mass of air, 28.8g, is higher than the molecular mass of nitrogen, 28g, the mass mixing ratio would be lower than the volume mixing ratio.

a) m=F/a m=101300/9.8=10,336 An estimate of the total mass of a column of the atmosphere with a base area of 1m2 is 10,336kg.

b) for a 1m2 column at average surface pressure of 985mb: m= 98500/9.8=10,051 kg
Surface area of the Earth:
4π (6370)^2=509,904,363.8
=5.1 x 〖10〗^8 〖km〗^2
=5.1 x 〖10〗^14 m^2

5.1x〖10〗^(14 ) x 10,051=5.13 x 〖10〗^18 kg

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