Reaction: HNO₃ + Cu → Cu(NO₃)₂ + NO + H₂O with oxidation states: +1+5-2 0 +2+5-2 +2-2 +1-2. Classify this reaction.

This is a redox reaction because there is a change in oxidation states of elements.

• Copper (Cu) is oxidized from 0 to +2.
• Nitrogen (N) in nitric acid is reduced from +5 to +2 in NO.

Answer: Redox reaction