Properties of Matter Flashcards
What is heat energy measured in?
Joules (J)
Define temperature.
A measure of how hot a substance is.
What is temperature measured in?
Celcius (°C)
What does the heat energy required to change the temperature of a substance depend on?
- The change in temperature of the material
- The mass of the material
- The type of the material
Define the SPECIFIC HEAT CAPACITY.
The specific heat capacity is the amount of energy required to change the temperature of 1kg of a substance by 1°C.
What is the unit for specific heat capacity?
Joule Per Kilogram
(J/kg°C)
What is the formula for finding heat energy?
Eh = cm∆T
Eh - Heat Energy (J)
c - Specific Heat Capacity (J/kg°C)
m - Mass (kg)
∆T - Change in temperature (°C)
What can the change in temperature mean?
The change in temperature can mean:
- The amount of heat energy required to increase the temperature of an object
- The amount of heat energy given out by an object as it cools
What is the law of Conversation of Energy?
The Law of Conservation of Energy states that ENERGY CANNOT BE CREATED OR DESTROYED, BUT CAN BE CHANGED FROM ONE FORM INTO ANOTHER.
What graph can be plotted to show how temperature varies over time?
A cooling curve.
What happens when a material changes state FROM GAS TO LIQUID, or LIQUID TO SOLID?
Latent heat is released.
What is latent heat?
Latent heat is “hidden” heat. It describes the heat released or absorbed during a change of state.
It is the energy required to change the state WITHOUT a change in temperature.
What is the formula for the total heat energy required to change the state of a material?
Eh=mL
—
Eh - Heat energy (J)
m - Mass [that has changed state] (kg)
L - Specific Latent Heat of Material (Jkg–¹)
What is pressure?
The force per unit exerted on a surface.
What is pressure measured in?
Pascals (Pa)
[1 Pa = 1Nm–²]
(1Nm-2 = 1 Newton per Metre²)
How is pressure affected when weight is concentrated on a very small area?
Larger pressure