CC11 · Quiz — Physical & Chemical Changes

Question 1

Which of the following is a PHYSICAL change?

ABurning of paper — new substances (CO2, H2O, ash) are formed

BRusting of iron — iron oxide (Fe2O3) is a new substance

CDissolving sugar in water — no new substance; sugar can be recovered by evaporation

DSouring of milk — lactic acid is formed by bacterial action

Question 2

A chemical change can be identified by which of the following observations?

AChange in size or shape of the substance

BChange in state (solid to liquid to gas)

CFormation of a new substance with different properties

DMixing of two substances without reaction

Question 3

Melting of ice is classified as a physical change because:

AEnergy is absorbed during the process, proving a new substance must form

BA new substance (liquid water) is produced with completely different properties

CNo new substance is formed — H₂O remains H₂O and the change is reversible

DThe change is irreversible since frozen water cannot be re-frozen once melted

CC11 — Physical & Chemical Changes — Quiz