Question

Suppose the elements x and y combine to form two compounds xy2 and x3y2. When 0.1 mole of xy2 weighs 10g and 0.05 mole of x3y2 weighs 9g, the atomic weight of x and y are

a) 40,30
b) 60,40
c) 20,30
d) 30,20

Answer 1

find the mole weights

x + 2y = 100

3x + 2y = 180

solve the system for x and y