CH4 + O2 --> CO2 + 2H2O

Question

What needs to be done to balance this equation?

A. Remove coefficient 2 in front of H2O on the right side of the equation.
B. Do nothing (equation is balanced).
C. Change O2 to O4 on the left side of the equation.
D. Add coefficient 2 to O2 on the reactant side of the equation.

Answer 1

The balanced equation is: CH4 + 2O2 --> CO2 + 2H2O

So the answer is:
D. Add coefficient 2 to O2 on the reactant side of the equation.