Suppose the elements P and Q combine to form two compounds P Q 2 and P 3 Q 2 . When 0.1 mole of P Q 2 weight 10 g and 0.05 mole of P 3 Q 2 weight 9 g, the atomic weights of P and Q are

Step-by-step solution

Let atomic weight of element P is p and that of element Q is q. For P Q 2 , n = w M o l . w t . 0.1 = 10 p + 2 q p + 2 q = 10 0.1 = 100 ...(i) For P 3 Q 2 , n = w M o l . w t . 0.05 = 9 3 p + 2 q 3 p + 2 q = 9 0.05 = 180 ...(ii) On solving equation (i) and (ii) we get q = 30 p + 2 ( 30 ) = 100 p = 100 - 60 = 40