Stoichiometry Practice

8 problems · instant feedback · full explanations

Stoichiometry turns a balanced equation into quantitative predictions. These eight problems cover mole-to-mole ratios, limiting reactants, and percent yield, with every calculation shown so you can follow the unit conversions.

Q1.
For the reaction 2H2 + O2 -> 2H2O, how many moles of H2O form from 4.0 mol of H2 reacting with excess O2?

Numerical answer (mol) · Easy

Q2.
3.0 mol H2 and 2.0 mol O2 react according to 2H2 + O2 -> 2H2O. Which reactant is limiting?

Multiple choice · Medium

Q3.
For C + O2 -> CO2, what mass of CO2 forms from 1.00 mol of carbon?

Numerical answer (g) · Easy

Q4.
The actual yield of a reaction can exceed its theoretical yield.

True / False · Easy

Q5.
A reaction has a theoretical yield of 50.0 g and an actual yield of 40.0 g. What is the percent yield?

Numerical answer (%) · Easy

Q6.
In 2H2 + O2 -> 2H2O, the mole ratio of O2 to H2O is:

Multiple choice · Easy

Q7.
For 2Al + 3Cl2 -> 2AlCl3, how many moles of AlCl3 form from 6.0 mol of Cl2 (excess Al)?

Numerical answer (mol) · Medium

Q8.
What is conserved in every balanced chemical reaction?

Multiple choice · Beginner

Stoichiometry Practice

Q1. For the reaction 2H2 + O2 -> 2H2O, how many moles of H2O form from 4.0 mol of H2 reacting with excess O2?

Q2. 3.0 mol H2 and 2.0 mol O2 react according to 2H2 + O2 -> 2H2O. Which reactant is limiting?

Q3. For C + O2 -> CO2, what mass of CO2 forms from 1.00 mol of carbon?

Q4. The actual yield of a reaction can exceed its theoretical yield.

Q5. A reaction has a theoretical yield of 50.0 g and an actual yield of 40.0 g. What is the percent yield?

Q6. In 2H2 + O2 -> 2H2O, the mole ratio of O2 to H2O is:

Q7. For 2Al + 3Cl2 -> 2AlCl3, how many moles of AlCl3 form from 6.0 mol of Cl2 (excess Al)?

Q8. What is conserved in every balanced chemical reaction?