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THERMAL ENERGY

Thermal energy is heat energy. In equation form, heat energy is represented as a (Q). The
unit for thermal energy is Joules (J). You can determine how much heat energy is lost or
gained when the temperature of a substance changes.

The equation to solve for change in thermal energy is ΔQ=CmΔT
Q=Thermal energy (J)
C= the specific heat of the object (g x°C)
m= mass (g)
T=temperature (°C)

Solve for change in thermal energy (Q) .

1. A 10.0 g piece of copper wire, sitting in the sun reaches a temperature of 80.0ºC. How
many Joules are released when the copper cools to 40.0ºC? The specific heat capacity of
copper is 0.377J/(gºC).

Q=?
C=
m=
Δt=

2. The specific heat capacity of water is 4.184 J/(gºC). How much thermal energy is
required to change the temperature of 700.0 g of water from 25.6ºC to 75.4ºC?

3. How much thermal energy is released when a 201 g piece of blown glass at an initial
temperature of 150ºC is cooled to 25ºC? The specific heat capacity of glass is 0.837
J/(gºC).

4. How much heat must be absorbed by a 500 g pot of water in order to raise the
temperature of the water from 20 °C to 30 °C? (specific heat capacity of water is 4.184
J/(g°C)

5. An element has a specific heat of 0.18 J/(gºC). If 10 g of this element are heated and release 345 J of energy, what would be the resulting change in temperature?

User Jarussi
by
3.1k points

1 Answer

15 votes
15 votes
1. Q=(10)(0.377)(40)
Q=150.8J

2. T= 75.4-25.6 = 49.8
Q = (700)(4.184)(49.8)
Q = 145854.24J

3. Q = (201)(0.837)(125)
Q= 21029.625J

4. Q = (500)(4.184)(10)
Q = 20920J
User Fred Wilson
by
2.8k points