Answer: +2.
- A −2
- B −1
- C +2
- D 0
Correct answer: C. +2
Explanation: Fluorine is more electronegative than oxygen, so each F is −1 and oxygen is forced to +2 in OF<sub>2</sub>.
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.