Energy and Heat Test Review
1. The study of heat changes that occur during chemical reactions is called
_thermochemistry_____________________
2. Explain the difference between heat and temperature: Temperature is a
measure of how much an energy a substance may have; Heat is the transfer
of energy due to a difference in temperature
3. ____Energy___________ is the the capacity to do work or supply heat
4. Contrast exothermic and endothermic – Exothermic – heat is transferred
from the system to its surroundings; Endothermic – heat is transferred
from the surroundings to the system
5. Two units of heat measurement are __Joules____ and _calories_________.
The conversion factor is __4.184 J = 1 calorie________________.
6. How much heat it takes to raise the temperature of an object by 1oC is
called _____heat capacity_________________. The two factors that
influence this are ___type_________ and ___amount of substance______.
7. The amount of energy required to raise the temperature of 1g of substance
by 1oC is __specific heat___ and the formula is __q=mCp∆T_____________
8. ___Calorimetry______________ is using the specific heat of something you
know to find the specific heat of something you don’t
9. Explain the Law of Conservation of Energy: Heat lost by one substance must
be equal to that gained by another substance
10. From the below heat curve, match the letter to the following terms:
Solid A
Freezing K
Melting D
Liquid E
Condensing J
Vaporization H
Melting Point B
Gas I
Heat of Fusion C
Boiling Point F
Heat of Vaporization G
11. Fill in the correct terms on the diagram below
12. What is the specific heat of a metal if a 40g sample at 110.0oC raises the
temperature of 300g of water from 23.2oC to 29.1oC?
q=300(4.184)(5.9)= 7405.68
Cp=-7405.68/(40*(29.1-110))= 2.26
13. What is the specific heat of a substance if a 45g sample at 101.5oC raises
the temperature of 154g of water from 20.6oC to 33.1oC?
q=154(4.184)(12.5)=8054.2
Cp=-8054.2/(45*(33.1-101.5))= 2.62
14. Granite has a specific heat of 800 J/g∙°C. What mass of granite is needed
to store 150,000 J of heat if the temperature of the granite is to be
increased by 15.5°C? m=150000/(800*15.5)= 12.1g
15. A total of 54.0 joules of heat are absorbed as 58.3 g of lead is heated from
12.0°C to 42.0°C. From these data, what is the specific heat of lead?
Cp=54/(58.3*30)= .03
16. How much energy is required to heat 120.0 g of water from 2.0 °C to 24.0
°C? (Cp of H2O = 4.184 J/g °C) q=120(4.184)(22)=11045.76
17. To what temperature will a 50.0 g piece of glass raise if it absorbs 5275
joules of heat and its specific heat capacity is 0.50 J/g°C? The initial
temperature of the glass is 20.0°C
∆T=5275/(50*.5)= 211
Final temperature = 20+211=231
18. How many joules of heat are needed to raise the temperature of 10.0 g of
aluminum from 22°C to 55°C, if the specific heat of aluminum is 0.90 J/g°C?
q=10(.9)(33)=297
19. How many joules of heat are needed to raise the temperature of 10.0 g of
aluminum from 22°C to 55°C, if the specific heat of aluminum is 0.90 J/g°C?
q=10(33).9=297
20. Calculate the specific heat capacity of a piece of wood if 1500.0 g of the
wood absorbs 67,500 joules of heat, and its temperature changes from
32°C to 57°C.
Cp=67500/(1500*25)=.19