Temperature Changes And Energy Flashcards
What are the particles in a solid like?
Regular arrangement
Vibrate around a fixed position
Sit very closely
What are particles in a liquid like?
Randomly arranged
Move around eachother
Sit close together
What are particles in a gas like?
Randomly arranged
Move quickly in all directions
Are far apart
How can adding or removing energy change a materials state?
Heating a solid makes it melt from solid to liquid
Continued heating causes it to evaporate
What is sublimation?
A solid going straight to a gas without being heated
What is boiling?
An active process
Do actively apply energy to a liquid to turn it into a gas using a heater like a kettle
What is evaporation?
A passive process of liquid turning into a gas
Liquid slowly absorbs energy from the surrounding area so some particles gain enough energy to escape the liquid
What happens to particles in a change of state?
Number of particles don’t change just their arrangement
Total mass doesn’t change
Why are changes in state physical changes?
Physical changes because the process can be reversed
What may happen internally when a material is cooled or heated?
Chemical bonds between particles may form break or stretch. There is a change in chemical potential store
As the material heats up or cools down particles gain or loose speed. There is a change in thermal store
What is internal energy?
Total amount of kinetic and chemical potential energy of all particles in the system
What happens to particles when energy is given to raise the temperature?
Particles speed up and gain kinetic energy
What happens to bonds when a substance melts or boils?
Energy is put into breaking bonds that hold particles together, which increases potential energy
Where does energy go in change of state?
All energy will go to the thermal or chemical store
What is temperature?
Measure of the average speed of particles. This is based on the kinetic energy of individual particles m
What does heating water to water molecules?
They gain kinetic energy and speed up
Why does it take more energy to raise the temperature of large amounts of water?
More molecules need to have their speed changed
Why is it quicker to heat a block of lead than water?
Because led is a solid and particles are vibrating and vibrate faster when heated the particles are more likely to hit eachother and pass energy
What is specific latent heat
Energy required to change the state of a 1kg of material without changing its temperature
What is latent heat of fusion?
Amount of energy needed to melt or freeze the material at its melting point
What is specific latent heat of vaporisation?
Amount of energy needed to boil or condense a material at its boiling point
In a temperature-time graph what does a long horizontal line mean?
More energy has been used to cause a change of state
Equal to the latent heat
