Pressure of 1 g of an ideal gas A 27^(@)C is found to be 2 bar. When 2 g of another ideal gas B is introduced in the same flask at same temperature, the pressure becomes 3 bar. Find the relationship between their molecular masses.

Pressure of 1 g of an ideal gas A 27^(@)C is found to be 2 bar. When 2

1.	Pressure of 1 g of an ideal gas A 27^(@)C is found to be 2 bar. When 2 g of another ideal gas B is introduced in the same flask at same temperature, the pressure becomes 3 bar. Find the relationship between their molecular masses.
Answer» Solution :Suppose molecular MASSES of A and B `M_(A)` and `M_(B)` respectively. Then their number of moles will be `m_(A)=(1)/(M_(A)),""n_(B)=(2)/(M_(B))` `P_(A)=2"BAR", P_(A)+P_(B)=3"bar",i.e.,P_(B)=1"bar"` Applying the relation, PV=nRT `P_(A)V=n_(A)RT,P_(B)V=n_(B)RT` `:."" (P_(A))/(P_(B))=(n_(A))/(n_(B))=(1//M_(A))/(2//M_(B))=(M_(B))/(2M_(A))` `"or" (M_(B))/(M_(A))=2XX(P_(A))/(P_(B))=2xx(2)/(1)=4"" or "" M_(B)=4M_(A)`.