Specific Heat Capacity

Temperature vs. Heat

• Temperature is the measurement of the avg. KE of the particles in matter.

• Heat energy that flows from a warmer object to a cooler object.

4

A. When you touch ice, heat is transferred from

1) your hand to the ice2) the ice to your hand

B. When you drink a hot cup of coffee, heat is transferred from

1) your mouth to the coffee2) the coffee to your mouth

Learning Check

Have you ever noticed that on a hot summer day the pool is cooler than the hot cement?

OR maybe that the ocean is cooler than the hot sand?

Specific Heat Capacity

1 calorie = 4.184 J1,000 J = 1 KJ4,184 J = 1 Kcal = 1 Calorie

Specific Heat: The amount of heat required to raise the temperature of 1 gram of a substance 1 degree Celsius.

Substance Specific Heat

J/(g°C)

Water 4.184Ethanol 2.44Aluminum 0.897Granite 0.803Iron 0.449

LecturePLUS Timberlake 99 10

Learning Check

A. A substance with a large specific heat 1) heats up quickly 2) heats up slowly

B. When ocean water cools, the surrounding air 1) cools 2) warms 3) stays the same

C. Sand in the desert is hot in the day, and cool at night. Sand must have a

1) high specific heat 2) low specific heat

Equation:

q = c x m x ΔTΔT = Tfinal – Tinitial

q = the heat absorbed or releasedc = the specific heat of the substancem = the mass of the sample in gramsΔT = change in temperature

1.) Copper metal has a specific heat (Cp) of

0.385 J/g⁰C. Calculate the amount of heat (J) required to raise the temperature of 22.8 g of copper from 20.0⁰C to 875⁰C.

2) What is the specific heat of a 25.0 g substance that absorbs 493.4 J, and raises the temperature from 12.0⁰C to 34⁰C?

3) It takes 1,250 J of energy to heat a certain sample of pure silver from 12.0 0C to 15.2 0C. Calculate the mass of the sample of silver.