When 2g of a gas A is introduced into an evacuated flask kept at 25°C, the pressure is found to be 1 atmosphere. If 3g of another gas is then added to the same flask, the total pressure becomes 1.5 atm. Assuming ideal behaviour, the ratio of their molecular weights M_(A): M_(B) is

When 2g of a gas A is introduced into an evacuated flask kept at 25°C

1.	When 2g of a gas A is introduced into an evacuated flask kept at 25°C, the pressure is found to be 1 atmosphere. If 3g of another gas is then added to the same flask, the total pressure becomes 1.5 atm. Assuming ideal behaviour, the ratio of their molecular weights M_(A): M_(B) is
Answer» `3:1` `1:3` `2:3` `3:2` SOLUTION :`(P_A)/(P_B) = (W_A)/(M_A) XX (M_B)/(W_B) = 1/3`.