Question

1. which of the following is the best example of a physical change?

• burning a piece of wood
• baking a cake
• rusting of an iron nail
• melting of an ice cube

Explanation:

To determine the best example of a physical change, we analyze each option:

• Burning wood: Chemical change (produces new substances like ash, CO₂).
• Baking a cake: Chemical change (ingredients react to form new compounds).
• Rusting of iron: Chemical change (iron reacts with oxygen to form rust, a new substance).
• Melting ice: Physical change (ice (solid H₂O) turns to liquid H₂O; no new substance is formed, just a state change).

Answer:

D. Melting of an ice cube