Question

HCl contains 97.26% chlorine, phosphine contains 91.1 % phosphorus. Applying the suitable law of chemical combination, calculate how much quantity of phosphorus will combine with 10.65 g of chlorine to form a compound?

Answer 1

In HCI, chlorine = 97.26 parts and hydrogen 2.74 parts So, 2.74 parts of hydrogen combine with chlorine = 97.26 parts
1 part of hydrogen combines with chlorine $=\frac{97.26}{7.26}$ parts = 35.5 parts
In phosphine, phosphorus = 91.1 parts and hydrogen = 8.9 parts
So, 8.9 pads of hydrogen combine with phosphorus = 91.1 parts .
1 part of hydrogen combines with phosphorus $=\frac{91.1}{8.9}=10.24$ parts
According to law of reciprocal proportions, when phosphorus and chlorine will react, they should combine in the ratio of 10.24: 35.5 by mass.
So, 35.5 g of chlorine combine with phosphorus = 10.24 g
10.65 g of chlorine will combine with phosphorus $=\frac{10.24}{35.5}\times 10.65g=3.072g$