Physical changes Flashcards
What happens when energy (heat is added to the particles of a solid?
The movement energy of the particles increases until it reaches melting point.
What happens if the movement energy of particles increase?
The forces between the particles weaken and the particles move further apart.
What happens if the particles of a solid receive enough energy?
The solid melts.
What happens when the material has melted completely?
The kinetic energy will start to increase again as the temperature increases and the particles will move even further apart.
What happens if the liquid particles have enough energy?
The forces between the particles will break, so it can move much further apart and it will change to the gaseous state.
How does the physical appearance of water change when energy is removed?
At room temperature, water is a colourless liquid. If energy is removed and it cools down to 0 degrees Celsius, it will freeze and become a colourless solid called ice.
How does the physical appearance of ice change when energy is added?
If ice is heated, it will change to water. The process is called melting.
How does the physical appearance of water change when energy is added?
Water will boil at 100 degrees Celsius. Steam forms, which is sometimes visible but disappears quickly into the atmosphere between the other air particles as a colourless gas.
What does freeze or solidify mean?
A material changes from liquid state to solid state.
What does boil mean?
The quick change from a liquid to a gas.
What is boiling point?
The temperature at which a liquid’s temperature will no longer increase. It is the temperature at which the material changes quickly from a liquid to a gas.
What is evaporation?
Evaporation can occur at any temperature to change a liquid into a gas.
What happens when gases cool down?
It forms a liquid again.
What is sublimation?
When a solid changes directly into a gas, e.g. dry ice.
What is deposition?
The opposite of sublimation. The material changes directly from a gas to a solid.
