A 2.00-g sample of an oxide of bromine is converted to 2.936 g of AgBr. Calculate the empirical formula of the oxide. (molar mass for AgBr = 187.78)

Question

Quizplus · Accepted Answer

The empirical formula of the oxide is BrO3.The molar mass of AgBr is 187.78 g/mol. So, 2.936 g of AgBr is equal to 2.936 g / 187.78 g/mol = 0.0156 mol of AgBr.Since AgBr is formed from the reaction of Ag+ and Br-, the number of moles of Br- in the oxide is also 0.0156 mol.The mass of Br- in the oxide is 0.0156 mol * 79.904 g/mol = 1.246 g.The mass of O in the oxide is 2.00 g - 1.246 g = 0.754 g.The number of moles of O in the oxide is 0.754 g / 16.00 g/mol = 0.0471 mol.The ratio of Br to O in the oxide is 0.0156 mol / 0.0471 mol = 1:3.Therefore, the empirical formula of the oxide is BrO3.

A 200-G Sample of an Oxide of Bromine Is Converted to to 2.936