Neutralize with Nitric Acid
React acid with bases and carbonates
What this lesson covers
Why it matters
Black copper oxide vanishes into a vivid blue solution upon meeting dilute nitric acid. The solid dissolves, leaving behind water and a copper nitrate solution.
The idea in plain words
Balance each neutralisation on the see-saw: CuO, NaOH and Na₂CO₃ all turn nitric acid into a nitrate salt — with water, and CO₂ from the carbonate.
Predict first
What happens when dilute nitric acid reacts with copper(II) oxide?
Nitric acid acts as a typical acid here, neutralizing the basic oxide to form a soluble blue nitrate salt and water.
- Black solid dissolves to form a blue solution — correct
- Black solid remains unchanged
- Brown gas is evolved immediately
- A green solution forms
What you do
Nitric acid neutralises a basic oxide, an alkali, and a carbonate — each gives a nitrate salt. Run all three (the carbonate fizzes off CO₂), then balance the equations on the see-saw.
Check yourself
Why does the black copper(II) oxide dissolve in dilute nitric acid?
Basic metal oxides such as CuO react with acids to form salt and water. Cu(NO₃)₂ is soluble and blue.
Which observation confirms the reaction between calcium carbonate and nitric acid?
Carbonates react with acids to produce CO₂ gas. CO₂ turns limewater milky due to the formation of calcium carbonate precipitate.
In the reaction NaOH + HNO₃ → NaNO₃ + H₂O, what type of reaction is this?
An acid (HNO₃) reacts with a base (NaOH) to form salt (NaNO₃) and water. This is the definition of neutralization.
- It is a neutralization reaction forming soluble copper nitrate — correct
- The acid physically washes the powder away
- Copper oxide is soluble in all liquids
- The acid reduces copper oxide to metallic copper
- Effervescence of a gas that turns limewater milky — correct
- Formation of a blue solution
- Evolution of hydrogen gas
- No visible change occurs
- Neutralization — correct
- Decomposition
- Displacement
- Redox