We have a mixture of two gases, say nitrogen and hydrogen. To calculate the average molar weight M , the formula says:
M (average) = (hydrogen pressure/100).M(H2) + ( 1 - nitrogen pressure/100).M(N2)
What I haven't understood is that why do we have pressure in the formula?
What I don't find logical as well is that the unit on the left side isn't the same as that on the right side of the equation.