Question

When very dilute nitric acid reacts with a strong reducing agent such as magnesium, the nitrate ion is reduced to ammonium ion. Write a balanced net ionic equation for the reaction. Include physical states in your answer.

Answer 1

When magnesium reacts with dilute nitric acid, nitrate is reduced to ammonium, resulting in the formation of ammonium nitrate and magnesium hydroxide. However, with concentrated nitric acid, magnesium reacts to form magnesium nitrate, nitrogen dioxide, and water.

Step-by-step explanation:

Net Ionic Equation for Dilute Nitric Acid with Magnesium

When very dilute nitric acid reacts with a strong reducing agent such as magnesium, nitrate ions are reduced to ammonium ions. The balanced net ionic equation for this reaction, including physical states, is:

Mg(s) + 2 HNO3(aq) + 8 H2O(l) → Mg(OH)2(s) + 2 NH4NO3(aq)

Reaction with Concentrated Nitric Acid

With concentrated nitric acid, instead of ammonium ions, nitrogen dioxide is produced. The balanced equation for the reaction of magnesium with concentrated nitric acid is:

Mg(s) + 4 HNO3(aq) → Mg(NO3)2(aq) + 2 NO2(g) + 2 H2O(l)