The H 2 produced in a chemical reaction is collected through water in a eudiometer. ?

Question

The H2 produced in a chemical reaction is collected through water in a eudiometer. If the pressure in the eudiometer is 760.0 torr and the vapor pressure of water under the experimental conditions is 19.7 torr, what is the pressure (torr) of the H2 gas?

Answer 1

Total pressure = pressure of H2 gas + pressure or H2O gas or put another way,

Total pressure = partial pressure of H2 gas + vapor pressure of H2O

Pressure of H2 gas = Total pressure - partial pressure of H2O

Pressure of H2 gas = 760.0 torr - 19.7 torr = 740.3 torr