This is an engaging activity to help students practice stoichiometry concepts by identifying and fixing the error in each problem. There are 8 questions provided, and students can do one or two per class as a bellringer, or they can do all 8 questions as a classwork assignment. Chemistry topics include balancing equations, moles, molar mass, mole-to-mole ratios, conversions in stoichiometry, limiting and excess reactants, percent yield, and percent error. There is a full answer key for these pra