Question

A 0.24 g sample of compound of oxygen and boron was found by analysis to contain 0.096g boron and 0.144g oxygen.Calculate the percentage composition of compound by weight.

Answer 1

Mass of compound = 0.24 g

Mass of boron = 0.096 g

%of boron = 0.096 × 100 × 100 / 0.24 ×1000

=40%

Mass of oxygen = 0.144 g

%of oxygen = 0.144×100×100/0.24×1000

=60%

Answer 2

Mass of compound = 0.24 g

Mass of boron = 0.096 g

% composition of boron = 0.096 × 100 × 100 / 0.24 ×1000

                                           =40%

Mass of oxygen = 0.144 g

%of oxygen = 0.144×100×100/0.24×1000

                     =60%