What is sublimation?
The chemical change from solid directly to gas
The chemical change from gas to solid
The physical change from gas to solid
The physical change from solid directly to gas
The internal energy of a system is equal to the total kinetic energy and potential energy in particles in the system.
True
False
What can happen to a system when its internal energy increases?
The temperature will rise or the system will change state.
The system will change state.
The temperature will rise.
The solid will become a gas.
Explain why a change of state can happen if a substance is cooled.
The particles gain energy and form bonds.
The particles gain energy and break bonds.
The particles lose energy and form bonds.
The particles lose energy and break bonds.
During which two changes of state does gas become a liquid?
Sublimation and melting
Evaporation and crystallisation
Boiling and evaporation
Boiling and condensation
Why does heating a system makes the particles move faster?
It transfers energy to the particles' chemical potential.
It transfers energy away from the particles.
It transfers energy away from the system.
It transfers energy to the particles' kinetic energy stores.
What is meant by "physical change"?
New substances are formed.
A chemical reaction has happened.
No new substances are formed.
The process is irreversible.
The internal energy of a system is equal to the total kinetic energy in particles in the system.
True
False
The more energy in the kinetic energy store of a particle the...
Faster it moves.
Slower it moves.
Why is mass conserved when a substance changes state?
Energy cannot be destroyed or created, only transferred.
The number of particles changes.
The number of particles stays the same.
What is meant by "physical change"?
The substance cannot recover its original properties.
The substance can recover its original properties.