1. The difference between heat and temperature
Introducing ‘internal energy’. Measured in joules it gives an indication of the sum of all the random potential and kinetic energies of all the particles in a system.
Temperature on the other hand is a quantifiable measure of how hot or cold an object is and is related to the average kinetic energy of the particles in a substance.
2. How temperature changes with Internal Energy
As you heat up a substance its internal energy will increase. The temperature will also rise but not at a uniform rate.
For a pure substance there will be periods where the internal energy rises but the temperature does not. As the substance changes phase any energy supplied goes into breaking apart bonds rather than increasing the kinetic energy of the molecules.