Balancing Chemical Equations Practice
8 problems · instant feedback · full explanations
A balanced equation has the same number of each atom on both sides. These eight problems build the skill step by step, from reading coefficients to balancing full equations and spotting the mistakes that break the law of conservation of mass.
Q1.
Which set of coefficients balances CH4 + O2 -> CO2 + H2O (in the order CH4, O2, CO2, H2O)?
Multiple choice · Medium
Q2.
In the balanced equation 2H2 + O2 -> 2H2O, what is the coefficient of O2?
Multiple choice · Easy
Q3.
A balanced equation conserves atoms, but the total number of molecules may change.
True / False · Beginner
Q4.
Balance N2 + H2 -> NH3. The coefficients (in order) are:
Multiple choice · Easy
Q5.
Changing subscripts in a chemical formula is an acceptable way to balance an equation.
True / False · Beginner
Q6.
In the balanced equation 2Mg + O2 -> 2MgO, the coefficient of MgO is:
Multiple choice · Easy
Q7.
The balanced equation for propane combustion is C3H8 + 5O2 -> 3CO2 + 4H2O. What is the sum of all four coefficients?
Numerical answer · Medium
Q8.
An unbalanced chemical equation violates which law?
Multiple choice · Easy