### This is an **oxidation-reduction** (redox) reaction:

** *** NaI + e- → Na0 (reduction)*

*NaI + e- → Na0 (reduction)*

* NIII - 1 e- → NIV (oxidation)*

*NIII - 1 e- → NIV (oxidation)*

*NaNO2* is an **oxidizing** agent, *NaNO2* is a **reducing** agent.

*NaNO2*

*NaNO2*

### Word equation

* sodium nitrite → sodium + nitrogen dioxide*

### Input interpretation

* NaNO2 → Na + NO2*

** Sodium nitrite nitrogen nitrogen dioxide**

### Balanced equation

Balance the chemical equation algebraically:

* NaNO2 → Na + NO2*

Add stoichiometric coefficients, c;, to the reactants and products:

* c1 NaNO2 → c2Na + c3NO2*

Set the number of atoms in the reactants equal to the number of atoms in the products for** N, Na **and **O:**

*N: c1=c3*

*Na: c1=c2*

*O: 2c1 = 2c3*

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=1 *

* c3 = 1*

Substitute the coefficients into the chemical reaction to obtain the balanced

equation:

Answer:

* NaNO2 → Na + NO2*

### Word equation

* sodium nitrite → sodium + nitrogen dioxide*