Question

part 1: definitions
physical change – a change that affects the form or appearance of a substance, but does not change what the substance is.
the substance is the same after the change.
examples: cutting paper, melting ice, boiling water.
chemical change – a change that forms a new substance with new properties.
the substance is different after the change.
examples: rusting iron, burning wood, baking a cake.

part 2: clues to identify a chemical change
look for these clues that a chemical change may have occurred:
color change
gas production (bubbles, fizzing)
temperature change (without heating/cooling)
formation of a solid (precipitate)
new smell or light produced

part 3: practice — identify each as physical or chemical
write p for physical change or c for chemical change.

change description p or c?

1 ice melting into water
2 wood burning in a campfire

Explanation:

For Question 1 (Ice melting into water):

Step1: Recall physical change definition

A physical change affects form/appearance but not the substance. Ice melting to water: ice (solid H₂O) becomes water (liquid H₂O). The substance (H₂O) remains the same.

Step2: Classify the change

Since the substance (water) is unchanged, it's a physical change. So we use "P".

For Question 2 (Wood burning in a campfire):

Step1: Recall chemical change definition

A chemical change forms a new substance. Burning wood: wood (cellulose, etc.) reacts with oxygen, forming ash, CO₂, etc. New substances are created.

Step2: Classify the change

As a new substance is formed, it's a chemical change. So we use "C".

Answer:

1. P
2. C