Test 3 MT Flashcards
What is the internal energy of a substance
The energy stored by the particles
The sum of the total kinetic and potential energies that make up the system
How does heating effect the energy of a substance
Heating transfers energy to the substance
It increases the energy of the particles that make up the substance
What 2 things can heating a substance do
Raise its temperature
Change the state of the subsatace
What 3 factors determine the temperature of a system
Mass of substance being heated
Type of material (specific heat capacity)
Energy inputted into the system
Specific heat capacity=?
Energy/mass*change in temperature
Define specific heat capacity
The amount of energy needed to increase the temperature of 1kg of a substance by 1 degree Celsius
Describe how the internal energy and temperature of a substance changes when a change of state occurs
The internal energy of the substance will be increased or decreased
The temperature of the substance will remain constant
Define specific latent heat
The amount of energy needed to change the state of 1kg of a substance with no change in temperature
Energy to change state=?
Mass * specific latent heat
What is the specific latent heat of fusion
The energy required to change 1kg of a substance from solid state to liquid state without changing the temperature
What is the specific latent heat for vaporisation
The energy required to change 1kg of a substance from liquid state to gas state (vapour) without a change in temperature
Describe the motion of molecules in a gas
They are in a constant random motion
What factor affect the average kinetic energy of gas molecules
The temperature of the substance
The higher the temperature, the higher the average kinetic energy of the molecules
What effect does increasing temperature have on the pressure of a gas when held at a constant value
Pressure of the gas will increase as the temperature increases
Why does pressure increase as temperature increases (at a constant volume)
Kinetic energy of molecules increases
Collisions between molecules become more frequent
Greater rate of change of momentum
Greater force and therefore pressure
