How many grams of excess reactant are left over after the reaction is complete?
The reaction occurs between equal numbers of moles of reactants. As a result, to find the mass of the excess reactant, the following equation can be used:
m = n × Mr
where m - mass, n - number of moles of the reactant left over after the reaction ( n = ni - nr, where ni - initial number of moles, nr - number of moles used in the reaction), Mr - molecular weight of the reactant.