P = (n2 /V) R T
(1 40)
Here V is volume of a solution in litres containing n2 moles of solute If w2 grams of solute, of molar mass, M2 is present in the solution, then
n2 = w2 / M2 and we can write,
P V =
2
2
 
 
 
w
MR T
(1 41)
or M2 =
∏
w2  
R T
V
(1