Pressure exerted by saturated water vapour is called aqueous tension. What correction term will you apply to the total pressure to obtain pressure of dry gas?

The gas collected over water is called moist and pressure exerted by saturated water vapour is called aqueous tension.

The total pressure of the gas is P _{moist gas} = P _{dry gas}

As exerted water vapour is present i.e. aqueous tension.Which is correction term from total pressure.

By applying this correction term we get a new equation,shown below -

P _{dry gas} =P _{moist gas} – aqueous tension

Therefore, the correction term applied to the total pressure of the gas to get the pressure of dry gas is P _{moist gas} – aqueous tension