Energy, Heat, and Calorimetry Study Guide

Energy

The ability to do work or produce heat.

Potential energy

Stored energy based on composition or position; the potential for doing work.

Kinetic energy

The energy of motion, dependent on an object's mass and velocity.

Temperature

A measure of the average kinetic energy of particles.

Heat (SI units)

Joules (J)

Mass (SI units)

Grams (g)

Temperature (SI units)

Degrees Celsius (°C)

Specific Heat (SI units)

J/g°C

Specific heat (Cp) of water

4.18 J/g°C

Cp (specific heat)

The amount of heat required to raise the temperature of 1 gram of a substance by 1°C.

Density of water

1.00 g/mL

Calorie

The amount of heat required to raise the temperature of 1 gram of water by 1°C.

Conversion between calories and joules

1 calorie = 4.18 joules

Calorimeter

A device used to measure heat absorbed or released during a chemical or physical process.

Law of Conservation of Energy

Energy is neither created nor destroyed; it is only transferred or transformed.

Direction of heat flow

From a warmer object to a cooler object.

Temperature when heat is gained

Temperature increases.

Temperature when heat is lost

Temperature decreases.

Endothermic process

A process that absorbs heat from the surroundings.

Exothermic process

A process that releases heat to the surroundings.

Equation for calculating heat (Q)

Q = m × Cp × ∆T

Q in Q = m × Cp × ∆T

Heat gained or lost (in joules)

m in Q = m × Cp × ∆T

Mass (in grams)

∆T in Q = m × Cp × ∆T

Change in temperature = T_final - T_initial

Cp in Q = m × Cp × ∆T

Specific heat (in J/g°C)

Kelvin conversions for temperatures

0°C = 273 K