Potassium chloride is used as a substitute for sodium chloride for individuals with high blood pressure. identify the limiting reactant and determine the mass of the excess reactant remaining when 7.00 g of chlorine gas (mm = 70.90 g/mol) reacts with 5.00 g of potassium (mm = 39.10 g/mol) to form potassium chloride. the reaction is

The reaction between chlorine gas (Cl2) and potassium (K) in order to form potassium chloride (KCl) is written below.

2K + Cl2 à 2KCl

We are to calculate the amount of product produce per given mass of reactant.

(7 g of chlorine gas)

(7 g Cl2) x (1 mol Cl2/70.90 g Cl2) x (2 mol KCl/1 mol Cl2) = 0.197 mols Cl2

(5 g of potassium)

(5 g K) x (1 mol K/39.10 g K) x (2 mol KCl/2 mol K) = 0.127 mols Cl2

Since, the calculate mols of Cl2 for 5 g of potassium is lesser then, the limiting reactant is potassium.