Physical changes such as state change and dissolving are reversible, and there is no change in total mass when they happen. Flowing and diffusion happens in liquids and gases, but not in solids.
What happens to the particles when a piece of rock is heated up?
They get bigger
They get smaller
They stay the same size
What happens to a bar of steel when it is cooled down?
It gets longer
It gets shorter
It stays the same length
What happens to the pressure in a metal spray can when it is heated up?
It stays the same
Why do gases exert a pressure on the walls of their container?
The gas particles hit each other
The gas particles move quickly in all directions
The gas particles hit the container walls
What process causes smelly gases to spread around a room on their own?
In which state are atoms closest together (except water)?
In which state do atoms have the most energy?
What is the transition from a solid to a gas called?
What happens to temperature when a state change occurs?
In which state is water most dense?