Atoms and Molecules –  Solutions

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

Solution:

Percentage is always calculated for 100

Percentage of an element = Mass of element/Mass of compound x 100

∴ Percentage of boron = Mass of boron/Mass of compound x 100

Mass of boron = 0.096g

Mass of oxygen = 0.144g