Easily calculate the pressure of any individual gas in a mixture using total pressure and mole fractions with Dalton's Law.
Dalton's Law of Partial Pressures states that in a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of the individual gases.
The mathematical expression is:
Ptotal = P1 + P2 + P3 + ... + Pn
Where each partial pressure (Pi) can be calculated as:
Pi = Xi × Ptotal
Xi is the mole fraction of gas i in the mixture.
Given a gas mixture with total pressure of 1 atm containing:
The partial pressures would be:
The sum is 0.78 + 0.21 + 0.01 = 1.00 atm, which matches the total pressure.