internal energy + shc

What is internal energy?

The total kinetic and potential energy of the particles in a substance.

What contributes to the kinetic energy of particles?

Their movement — faster movement means higher kinetic energy.

What contributes to the potential energy of particles?

Their positions and spacing — particles further apart have higher potential energy.

What happens to internal energy when a substance is heated?

Internal energy increases because particles move faster and/or move further apart.

What happens to internal energy when a substance is cooled?

Internal energy decreases because particles slow down and/or move closer together.

What happens to the kinetic energy of particles when temperature increases?

Kinetic energy increases.

What happens to the potential energy of particles during melting?

Potential energy increases as particles move further apart.

What happens to the potential energy of particles during freezing?

Potential energy decreases as particles move closer together.

What is the relationship between temperature and kinetic energy?

Temperature is proportional to the average kinetic energy of particles.

Why does heating a substance not always increase its temperature?

Energy may be used to change the state instead of increasing kinetic energy.

What is specific heat capacity (SHC)?

The energy needed to raise the temperature of 1 kg of a substance by 1°C.

State the equation for specific heat capacity.

Energy = mass × specific heat capacity × temperature change.

What are the units of specific heat capacity?

J/kg°C.

Why do different materials heat up at different rates?

They have different specific heat capacities.

Why does temperature stay constant during melting or boiling?

Energy is used to break bonds instead of increasing kinetic energy.