Thermochemistry Specific Heat Specific Heat n Amount of

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Thermochemistry Specific Heat

Thermochemistry Specific Heat

Specific Heat n Amount of heat it takes to raise 1 g of How

Specific Heat n Amount of heat it takes to raise 1 g of How easy or hard an object a substance by 1°C is to heat up – how fast does it absorb heat energy q q Metals have a low specific heat Water has a high specific heat

Learning Check 1. On a sunny day, the concrete deck around an outdoor swimming

Learning Check 1. On a sunny day, the concrete deck around an outdoor swimming pool becomes hot, while the water stays cool. This is because… A. The deck has a higher specific heat than the water B. The deck has a lower specific heat then the water C. Both objects have the same specific heat

Learning Check 2. Two objects are sitting next to each other in the sunlight.

Learning Check 2. Two objects are sitting next to each other in the sunlight. Object A gets hotter than object B. A. Object A has a lower specific heat than object B B. Object A has a higher specific heat than object B C. Both objects have the same specific heat

Specific Heat of Water Matches definition: Amount of heat it takes to raise 1

Specific Heat of Water Matches definition: Amount of heat it takes to raise 1 g of a substance by 1°C 4. 18 J/g × °C or 1 cal/g × °C

Formula for Specific Heat q = mc ΔT q = amount of heat –

Formula for Specific Heat q = mc ΔT q = amount of heat – measured in cal or J m = mass – measured in g C = specific heat – units are J/g x °C or cal/g x °C ΔT = change in temp – measured in °C

Specific Heat Problems: 1. Aluminum has a specific heat of 0. 9020 J/g ×

Specific Heat Problems: 1. Aluminum has a specific heat of 0. 9020 J/g × °C. How much heat is lost when a piece of aluminum with a mass of 23. 984 g cools from a temperature of 415. 0°C to a temperature of 22. 0°C? 2. 850 calories of heat are applied to a 250 g sample of liquid water with an initial temperature of 13. 0 °C. Find: a) the change in temperature and b) the final temperature. (remember, the specific heat of liquid water, in calories, is 1. 00 cal/g x °C. )

Specific Heat Problems: 3. The temperature of a sample of water increases by 69.

Specific Heat Problems: 3. The temperature of a sample of water increases by 69. 5 °C when 24, 500 J are applied. The specific heat of liquid water is 4. 18 J/g x °C. What is the mass of the sample of water? 4. When 34, 700 J of heat are applied to a 350 g sample of an unknown material the temperature rises from 22. 0°C to 173. 0°C. What must be the specific heat of this material?