Question

What is the pressure of the dry gas alone ?

Answer 1

P O₂ = 736.2 torr

Further explanation

Given

P tot=760 torr

P H₂O = 23.8 torr

Required

P gas/O₂

Solution

Dalton's law of partial pressures stated that

the total pressure of a mixture of gases is equal to the sum of the partial pressures of the component gases  

Can be formulated:  

P tot = P1 + P2 + P3 ....  Pn

P tot = P H₂O + P O₂

760 torr = 23.8 torr + P O₂

P O₂ = 760 - 23.8

P O₂ = 736.2 torr