Changes of State Flashcards

All 6 cards in this deck

What is sublimation?

A substance changing directly from solid to gas without becoming a liquid.

What name is given to the change from gas to liquid?

Condensing (condensation).

Which change of state is the reverse of melting, and at what temperature does it happen?

Freezing, at the same temperature as the melting point.

What happens to the mass of a substance when it melts, boils, condenses or sublimates?

Mass is conserved — it stays the same, because no particles are created or destroyed.

How does a physical change of state differ from some chemical changes?

A change of state is reversible — the material recovers its original properties if the change is reversed.

True or false? When water in an open beaker boils away, mass has been lost.

False. Mass is conserved; the water has become steam of the same mass, which has escaped into the air.