quiz 18 Flashcards
Explain why increasing the temperature of a gas increases the gas pressure
Particles have more kinetic energy and move faster so collide more often with a greater force
When kinetic energy of the particles in a substance decreases,what happens to the substance?
Temperature decreases
Which part of internal energy relates to changes of temperature ?
Kinetic energy
State the unit of specific heat capacity?
J/kg Celsius
What happens to the density of a substance when its heated and expands
Decreases
Describe the motion of particles in a gas
Move freely and randomly with a range of speeds and directions
Why do substances usually get less dense when heated?
The particles gain kinetic energy and move further apart
Why can gases be compressed?
There is space between the particles
Latent heat of vaporisation relates to which state change?
Liquid to gas or boiling
Why is mass conserved during state changes?
No particles are added or taken away
Define the specific latent heat of fusion of a substance
Amount of energy needed to melt 1 kg of the substance with no change in temperature
Why are solids usually the best conductors of heat and electricity?
The particles are closely packed
Are changes of state reversible or irreversible?
Reversible
What piece of equipment allows length to be measured much more accurately than a ruler?
Micrometer
What is a system?
A group of interacting parts
