Dalton’s Law states the principle that the pressure exerted by a mixture of gases in a fixed volume is equal to the sum of the pressures that each gas would exert if it occupied the whole volume Also called as Dalton's law of partial pressures. Calculate the pressure of combined gases with known values of temperature and mole of gas.
P_{tot}=p_{1}+p_{2}+p_{3}+...+p_{m} (or)
p_{tot}={n_{1}+n_{2}+n_{3}+...n_{m}}RT/v
Where,
p_{1},p_{2},p_{3}, ...,pm= Partial pressures of the individual gases in the mixture.
V = volume,
T = temperature,
n_{1},n_{2},n_{3}, ...,n_{m}= n is the total amount of gas of the m gases present in the mixture,
R = 8.314 J K-^{1} mol-^{1}, ideal gas constant.
"The Pressure of the mixture gas is equal to the sum of the pressure of the partial gases in a container'' is the statement of Dalton's partial pressures law. This empirical relation was stated by the English chemist John Dalton in 1801. It follows from the kinetic theory of gases under the assumption of a perfect (ideal) gas and assumes no chemical interaction between the component gases. It is approximately valid for real gases at sufficiently low pressures and high temperatures.
Example:
Calculate the Partial Pressure by using Dalton’s Law.
Dalton’s Law:
Enter the values of 'moles of gases (n)' separated by comma = 250
Temperature (T): 25 K
Moles of Gas (n): 250 moles
Volume (V): 5 L
Solution:
Apply Formula:
P_{tot}=p_{1}+p_{2}+p_{3}+...+p_{m}(or)
ptot={n_{1}+n_{2}+n_{3}+...n_{m}}RT/v
Pressure (P): 10392.5 kPa