Question

HNO3 + H3PO₃ = NO+H3PO4 + H2O Help me equalize this equation PLEASE!!

Answer 1

Answer:

2HNO₃ + 3H₃PO₃ ⟶ 2NO + 3H₃PO₄ + H₂O

Explanation:

HNO₃ + H₃PO₃ ⟶ NO + H₃PO₄ + H₂O  

One way is to balance this equation is the oxidation number method.

Step 1. Calculate the oxidation number of every atom:

H⁺¹N⁺⁵O₃⁻² + H₃⁺¹P⁺³O₃⁻² ⟶ N⁺²O⁻² + H₃⁺¹P⁺⁵O₄⁻² + H₂⁺¹O⁻²

Step 2. Identify the changes in oxidation number:

N: +5 ⟶ +2; Change =  -3

P: +3 ⟶ +5; Change = +2

Step 3. Equalize the changes in oxidation number.

You need 3 atoms of P for every 2 atoms of N. This gives us total changes of +6 and -6.

Step 4. Insert coefficients to get these numbers.

2HNO₃ + 3H₃PO₃ ⟶ 2NO + 3H₃PO₄ + H₂O

Step 5. Balance O.

We have fixed 15 O on the left and 14 O on the right. We need 1 more O on the right. Put a 1 in front of H₂O.

2HNO₃ + 3H₃PO₃ ⟶ 2NO + 3H₃PO₄ + 1H₂O

Every formula now has a coefficient. The equation should be balanced.

Step 6. Check that all atoms balance.

Atom  Left-hand side  Right-hand side

 H                 11                          11

 N                  2                          2

 O                15                         15

 P                  3                          3

All atoms balance.

The balanced equation is

2HNO₃ + 3H₃PO₃ ⟶ 2NO + 3H₃PO₄ + H₂O