Heat

Definition

Heat is a form of energy transfer between systems or objects with different temperatures. It flows from the hotter object to the cooler one until thermal equilibrium is reached.

5 Must Know Facts For Your Next Test

1. Heat transfer can occur through conduction, convection, and radiation.
2. The SI unit of heat is the joule (J), though calories are also commonly used.
3. Specific heat capacity is the amount of heat required to raise the temperature of one kilogram of a substance by one degree Celsius.
4. Calorimetry experiments measure the amount of heat transferred in physical and chemical processes.
5. $Q = mc\Delta T$ is the formula for calculating heat transfer, where $Q$ is heat, $m$ is mass, $c$ is specific heat capacity, and $\Delta T$ is the change in temperature.

Review Questions

• What are the three methods of heat transfer?
• How do you calculate the amount of heat transferred using specific heat capacity?
• What does calorimetry measure in thermodynamic processes?

Related terms

Conduction:

The process by which heat energy is transmitted through collisions between neighboring molecules or atoms.

Convection:

The transfer of heat by the movement of fluids (liquids or gases) caused by molecular motion.

Radiation:

The transfer of energy through electromagnetic waves without requiring a medium.