Specific Heat

Thinking About it…

When you are boiling water on a stove what heats up faster?

A. Water in the pot

B. The stove top

Why do you think?

Thinking About it…On a hot summer day at the beach which will be

hotter??

A. Sand

B. The water in the ocean

Specific Heat

• The measurement of how much heat is required to change the temperature of a unit mass of a substance by 1 degree is called its specific heat. (Or how fast something heats up and cools down)

• The specific heat is an important part of energy since it tells you how much energy (or calories) are needed to move each gram of the substance one degree.

• Every substance has its own specific heat

Specific Heat• Every substance has its

own specific heat or its own amount of heat energy needed to raise a given mass 1 degree Celsius.

• So by looking at the chart you can see that it would take water it would take twice as many calories to heat some water one degree than it would to heat the same mass of ice one degree.

ItemSpecific heat in cal/g-C

Ice 0.50

Water 1.00

Which item would take more energy to heat up?

a. Water

b. Steam

Given the same amount of energy which would take longer to heat up or cool down?

a. Water

b. steam

ItemSpecific heat in cal/g-C

Steam 0.48

Water 1.00

Water’s Specific Heat

• Compared with most other substances, water has an unusually high specific heat.

• Water resists changing its temperature; when it does change its temperature, it absorbs or loses a relatively large quantity of heat

• The reason you can burn your finger by touching the metal handle of a pot on the stove when the water in the pot is still lukewarm is that the specific heat of water is ten times greater than that of iron

What does waters’ specific heat have to do with Earth?

• A large body of water can absorb and store a huge amount of heat from the sun in the daytime and during summer from a small temperature increase.

• At night and during winter, the gradual cooling water can warm the air as the heat is released.

How would that affect the climate of coastal areas??

• Because of water being able to hold and release a large amount of heat , coastal areas generally have milder climates than inland regions.

• The specific heat of water affects the climate of coastal land!

• The high specific heat of water makes ocean temperatures quite stable, therefore making the climates of the coastal areas more stable as well.

How would that affect the climate of coastal areas??

• During day time, the land is heated more from the sun. The heated air rises and the relatively cool air from the sea moves over the adjoining land area to replace the rising air.

• The reverse thing happens at night. So the days are cooler and nights are warmer in coastal regions making a moderate climate throughout the year.