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