Question

3.15g compound of P and Q found to contain 0.42g P. 9.12g compound of the same element found to contain 7.41g Q. Which law can be illustrated?

Answer 1

The amount of p in compound 1 = 0.42g

The amount of Q in compound 1 = 3.15-0.42 = 2.73g

Ratio of masses of P and Q = 42:273 = 2:13

The amount of Q in compound 2 = 7.41

Amount of P in compound 2 = 9.12-7.41 = 1.71g,  Ratio of P and Q in 2nd compound = 171:741= 3:13.  The amount of Q is fixed so ratio of P combined with fixed mass of Q = 2:3 is a simple whole number ratio. This is LAW OF MULTIPLE PRPOPORTION