Question

What factors affect the vapor pressure of a liquid?

Answer 1

`ln(P_(vap))=-(DeltaH_(vap))/R(1/T)+C`

Explanation:

The expression of vapour pressure is given by:

`ln(P_(vap))=-(DeltaH_(vap))/R(1/T)+C`

where, `DeltaH_(vap)` is the enthalpy of vaporization and it is a constant for a specific liquid.

`R` is the universal gas constant: `R=8.3145 J/(mol.K)`.

`T` is the temperature and `C` is a constant.

Therefore, looking at the aforementioned expression, the only variable that affects the vapour pressure is temperature .