Which metal among aluminium, iron, copper, zinc is the least reactive?

• A. Aluminium
• B. Iron
• C. Copper
• D. Zinc

Answer: (C)

The main idea here is the reactivity series: metals are arranged by how easily they lose electrons and react with other substances. The more reactive a metal, the more readily it will displace other elements or react with acids and water. In this lineup, copper is placed lowest among aluminium, zinc, and iron, meaning it is the least eager to undergo oxidation. That’s why it doesn’t react readily with acids to release hydrogen gas and is less prone to corrosion compared with the others. Aluminium and zinc and iron are more reactive, with aluminium often appearing reactive even though it forms a protective oxide layer; copper, being lower in the series, shows the least reactivity. So copper is the least reactive of the four.