Which of the following statement is incorrect about heat?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Heat decreases the volume of matter.
Heat makes the particles of matter move faster and spread apart, so matter generally expands on heating: rails, bridges and the mercury in a thermometer all grow longer or larger when warmed.
The other three statements are true effects of heat:
Option (1) — heat is a form of energy, and adding it raises the temperature of a body.
Option (3) — it changes the state (ice melts, water boils) and physical properties such as size and electrical resistance.
Option (4) — it brings about chemical changes, such as burning, cooking and the decomposition of limestone.