Question

Write a balanced chemical equation for heating potassium nitrate to produce potassium nitrite and oxygen.

Answer 1

Balanced equation: the chemical equation in which the number of atoms of each element on the reactant side as well as the product side are equal is known as a balanced equation.

Balancing the following chemical equation:

${\mathrm{KNO}}_3\stackrel{∆}{\to }{\mathrm{KNO}}_2+{\mathrm{O}}_2$

Steps to balance the chemical equation:

• Count the number of atoms of each element on either side. Now first balance the compound with the maximum number of atoms

A number of atoms of each element on the reactant side:

$\mathrm{K}=1,\mathrm{N}=1,\mathrm{O}=3$

A number of atoms of each element on the product side:

$\mathrm{K}=1,\mathrm{N}=1,\mathrm{O}=4$

• As the number of oxygen is not equal on both the reactant and product sides so we will first balance oxygen by multiplying Potassium nitrate (${\mathrm{KNO}}_3$) by 2 on the reactant side. The reaction becomes:
• $2{\mathrm{KNO}}_3\stackrel{∆}{\to }{\mathrm{KNO}}_2+{\mathrm{O}}_2$
• Now Multiply potassium nitrite on the product side by 2 so as to balance potassium, nitrogen, and oxygen atoms.

$2{\mathrm{KNO}}_3\stackrel{∆}{\to }2{\mathrm{KNO}}_2+{\mathrm{O}}_2$

Thus all atoms of reactant and product side are equal i.e.$\mathrm{K}=2,\mathrm{N}=2,\mathrm{O}=6$. Hence the equation is balanced.

$\underset{\mathrm{potassium}\mathrm{nitrate}}{2{\mathrm{KNO}}_3\left(\mathrm{s}\right)}\stackrel{∆}{\to }\underset{\mathrm{potassium}\mathrm{nitrite}}{2{\mathrm{KNO}}_2\left(\mathrm{s}\right)}+\underset{\mathrm{oxygen}}{{\mathrm{O}}_2\left(\mathrm{g}\right)}$