This is an oxidation-reduction (redox) reaction:
C-IV - 8 e- → CIV (oxidation)
4 O0 + 8 e- → 4 O-II (reduction)
CH4 is a reducing agent, O2 is an oxidizing agent.
Word equation
methane + oxygen → carbon dioxide + water
Input interpretation
CH4 + O2 → CO2 + H2O
Methane oxygen carbon dioxide water
Balanced equation
Balance the chemical equation algebraically:
CH4 + O2 → CO2 + H2O
Add stoichiometric coefficients, c;, to the reactants and products:
c1CH4 + c2O2 → c3CO2 + c4H2O
Set the number of atoms in the reactants equal to the number of atoms in the products for C, H and O:
C: c1 = c3
H: 4c1 = 2c4
O: 2c2 = 2c3 + c4
Since the coefficients are relative quantities and underdetermined, choose a coefficient to set arbitrarily. To keep the coefficients small, the arbitrary value is ordinarily one. For instance, set c1 = 1 and solve the system of equations for the remaining coefficients:
c1=1 c2=2
c3 = 1 c4=2
Substitute the coefficients into the chemical reaction to obtain the balanced equation:
Answer:
CH4 + O2 → CO2 + H2O