Step 1: When Nitrogen dioxide reacts with water , and Oxygen then it gives Nitric acid.

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 by 2 on the reactant side to balance atoms of Hydrogen and Oxygen on both sides.

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 by 4 on the product side to balance Hydrogen and Oxygen on both sides.

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 by 4 on the reactant side to balance Nitrogen and Oxygen atoms on both sides.

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:

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