In the reaction ZnO + C —> Zn + CO, C acts as

In the chemical reaction ZnO + C → Zn + CO, carbon (C) acts as a reducing agent [1]. This is a redox reaction where zinc oxide (ZnO) is reduced to metallic zinc by losing oxygen, while carbon is oxidized to carbon monoxide (CO) by gaining oxygen [2]. A reducing agent is a substance that reduces another reactant by donating electrons or removing oxygen, and in this process, the agent itself undergoes oxidation. Specifically, the oxidation state of carbon increases from 0 in its elemental form to +2 in carbon monoxide, indicating a loss of electrons [1]. Conversely, zinc's oxidation state decreases from +2 in ZnO to 0 in Zn, confirming its reduction. Therefore, carbon facilitates the reduction of zinc oxide, making it the reducing agent in this chemical process.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 3: Metals and Non-metals > ZnCO (s) ZnO(s) + CO (g) 3 2 → Heat > p. 51
2. [2] Science , class X (NCERT 2025 ed.) > Chapter 1: Chemical Reactions and Equations > CuO +H Cu+H O 2 2 → Heat (1.29) > p. 13