Question

# - Air at a temperature of 20 0C and 750 mm Hg has a relative humidity...

- Air at a temperature of 20 0C and 750 mm Hg has a relative humidity of 80%. Calculate,

(i)The molal humidity of the air

(ii)The molal humidity of this air if its temperature is reduced to 10 °C and pressure increased to 2000 mm Hg condensing out some of the water

(iii)Weight of water condensed from 1000 litre of the original wet air

Vapour pressure of water at 20 °C = 17.5 mm Hg

Vapour pressure of water at 10 °C = 9.2 mm Hg

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