Answer: +1.
- A -1
- B +1
- C 0
- D +2
Correct answer: B. +1
Explanation: Hydrogen has an oxidation state of +1 in most compounds, including water.
Electron transfer in a redox reaction: zinc loses electrons (oxidised, acts as reducing agent) and copper(II) ions gain those same electrons (reduced, acts as oxidising agent).
Concept context
Master electron transfer in chemistry: assign oxidation states, balance half-reactions, identify oxidising and reducing agents, and connect redox to everyday reactions.