Question

Complete and balance the equation

${\mathrm{NO}}_2+{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2\to$

Answer 1

Step 1: When Nitrogen dioxide $\left({\mathrm{NO}}_2\right)$ reacts with water $\left({\mathrm{H}}_2\mathrm{O}\right)$, and Oxygen $\left({\mathrm{O}}_2\right)$ then it gives Nitric acid$\left({\mathrm{HNO}}_3\right)$.

${\mathrm{NO}}_2+{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2\to {\mathrm{HNO}}_3$

Step 2: Balancing the given chemical equation step by step as:

1. Count the number of atoms on both the sides

Reactant	Product
N - 1	N - 1
O - 5	O - 3
H - 2	H - 1

Here, atoms of Nitrogen are balanced Hydrogen, and Oxygen atoms are not balanced on both sides.

2. Multiply $\left({\mathrm{H}}_2\mathrm{O}\right)$ by 2 on the reactant side to balance atoms of Hydrogen and Oxygen on both sides.

${\mathrm{NO}}_2+2{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2\to {\mathrm{HNO}}_3$

3: Count the number of atoms on both the sides

Reactant	Product
N - 1	N - 1
O - 6	O - 3
H - 4	H - 1

Here, an atom of Nitrogen is balanced but atoms of Hydrogen and Oxygen are not balanced on both sides.

4: Multiply $\left({\mathrm{HNO}}_3\right)$ by 4 on the product side to balance Hydrogen and Oxygen on both sides.

${\mathrm{NO}}_2+2{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2\to 4{\mathrm{HNO}}_3$

5: Count the number of atoms on both the sides

Reactant	Product
N - 1	N - 4
O - 6	O - 12
H - 4	H - 4

Here, atoms of Hydrogen are balanced but atoms of Nitrogen and Oxygen are not balanced on both sides.

6: Multiply $\left({\mathrm{NO}}_2\right)$ by 4 on the reactant side to balance Nitrogen and Oxygen atoms on both sides.

$4{\mathrm{NO}}_2+2{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2\to 4{\mathrm{HNO}}_3$

7: Count the number of atoms on both sides:

Reactant	Product
N - 4	N - 4
O - 12	O - 12
H - 4	H - 4

Now the equation is balanced as all the atoms are equal on both sides.

Answer:

Step 3: $4{\mathrm{NO}}_2+2{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2\to 4{\mathrm{HNO}}_3$