A 2.45-g sample of strontium completely reacts with oxygen to form 2.89 g of strontium oxide. Use this data to calculate the mass percent composition of strontium in strontium oxide.
Here, we have to calculate the mass percent composition of Sr in Strontium oxide.
The mass percent composition or mass percent of an element is that the percentage of the element present in compound’s total mass.
% mass = (mass of element in 1 mole of the compound) / (molar mass of the compound) x 100%
Mass of Sr = 2.45 g
Mass of strontium oxide = 2.89 g
Mass percent of Sr = x 100 = 84.77 %
The mass percent composition of Sr in SrO is 84.77%