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,

**is an oxidizing agent.**

*O2*### 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*