Chapter 10 Calorimetry, Specific Heat & Heat Capacity

Calorimetry

The measurement of heat changes.

Calorimeter

A device used to measure heat changes.

Specific heat (s)

The heat required to raise 1 g of a substance by 1°C.

Heat capacity (C)

The heat required to raise an object by 1°C.

Formula for heat using specific heat

q = msΔT.

What does m represent in the formula q = msΔT?

Mass.

What does s represent in the formula q = msΔT?

Specific heat.

What does ΔT represent in the formula q = msΔT?

Temperature change.

How do you calculate temperature change?

ΔT = Tfinal − Tinitial.

Coffee-cup calorimeter

A constant-pressure calorimeter.

In coffee-cup calorimetry, what is usually the system?

The reaction.

In coffee-cup calorimetry, what are usually the surroundings?

The water.

For an exothermic reaction, does the system gain or lose heat?

Lose heat.

For an exothermic reaction, do the surroundings gain or lose heat?

Gain heat.

Bomb calorimeter

A constant-volume calorimeter.

What type of reactions are commonly studied in bomb calorimeters?

Combustion reactions.

Why is a bomb calorimeter considered isolated?

No heat is exchanged with the surroundings.

What must be known before using a bomb calorimeter?

The calorimeter heat capacity.

What relationship exists between heat lost and heat gained?

qlost = -qgained.

Most common equation used in calorimetry problems

q = msΔT.