Particle model of matter Flashcards
What does density tell us?
It tells us the mass for a given volume.
What equation would you use when working out density?
……………………3 density (kg/m ) = mass / volume P = m / V
How would you work out the density of an irregular object? (4)
- Find the MASS of the object using a balance.
- Fill a EUREKA can with WATER.
- Place the object into the water. This will cause water to be DISPLACED and flow out of the can through the spout.
- Measure the VOLUME of water displaced (which is equal to the volume of the object).
- Then calculate the DENSITY of the object.
What is meant by internal energy?
It is the energy stored in a system by the particles.
During a change of state what is happening to the internal energy store of the system and the temperature?
We are INCREASING the internal energy store of the system but we are NOT chainging the temperature.
What is meant by the specific latent heat of fusion?
It is the energy required to change 1 kg of a substance from a SOLID to a LIQUID with NO CHANGE IN TEMPERATURE.
What is meant by the specific heat of vaporisation?
It is the energy required to change 1 kg of a substance from a LIQUID to a VAPOUR with NO CHANGE IN TEMPERATURE.
What equation links to energy for a change of state, mass and specific latent heat?
thermal energy for a change of state = mass x specific latent heat E = m x L
Describe what happens to the internal energy store of a liquid as its heated [2]
The internal energy store of the substance increases as energy is transferred by heating to the (kinetic and potential) energy stores of the particles.
Explain the shape of the line in graph below between points A and B.
The line is flat because a change of state is occuring and all energy transferred to the substance is being used to break intermolecular bonds and change the state of the substance, and not increase its temperature.
