WorksheetsThermochemistry
Total questions: 35
Worksheet time: 32mins
Name
Class
Date
1.
What is the SI unit of energy?
a)
joule
b)
enthalpy
c)
calorimeter
d)
specific heat?
2.
What is the heat content of a system at constant pressure?
a)
joule
b)
enthalpy
c)
calorimeter
d)
specific heat?
3.
What is a device used to measure the heat absorbed or released during a chemical or physical change?
a)
joule
b)
enthalpy
c)
calorimeter
d)
specific heat?
4.
What is the quantity of heat needed to change the temperature of 1 g of a substance by 1oC?
a)
joule
b)
enthalpy
c)
calorimeter
d)
specific heat?
5.
If a piece of aluminum is heated from 30.0oC to 50.0oC, what is the value of ΔT?
a)
293.0K
b)
20.0K
c)
0.0K
d)
80.0K
6.
What would likely happen if you were to touch the flask in which an endothermic reaction were occurring?
a)
The flask would probably feel warmer than before the reaction started.
b)
The flask would feel the same as before the reaction started.
c)
The flask would probably feel cooler than before the reaction started.
d)
None of these.
7.
A piece of metal is heated, then submerged in cool water. Which statement below describes what happens?
a)
The temperature of the metal will increase.
b)
The temperature of the water will increase and the temperature of the metal will decrease.
c)
The temperature of the water will increase.
d)
The temperature of the water will decrease.
8.
Which of the equations below is an example of a thermochemical equation?
a)
Mg + 2H3O+ + Cl- → Mg2+ + 2Cl- + H2 + H20
→
→
b)
2H2(g) + 2O2(g) → H2O(g)
c)
Mg(s) + 2H3O+(aq) + Cl-(aq) → Mg2+(aq) + 2Cl-(aq) + H2(g) + H20(l)
d)
2H2(g) + 2O2(g) → H2O(g) + 483.6 kJ
9.
Which of the following best describes energy in the form of heat?
a)
a measure of the average kinetic energy of the particles in a sample of matter
b)
the energy transferred between samples because of a difference in their temperatures
c)
bond energy
d)
the energy stored in a sample of matter
10.
How much energy is needed to raise the temperature of 58.6 g of argon from 23.4oC to 55.6oC? The specific heat capacity of argon 0.520 J/g⋅K.
a)
981 J
b)
1671 J
c)
1887 J
d)
3.50 J
11.
A process that releases heat is a(n)
a)
ectothermic process
b)
exothermic process
c)
endothermic process
d)
polythermic process
12.
The greater the average kinetic energy of the particles in a sample of matter
a)
the more energy is absorbed by the sample in the form of heat.
b)
the less energy is released by the smaple in the form of heat.
c)
the lower the temperature is.
d)
the higher the temperature is.
13.
What is the energy required to raise the temperature of 1 g of a substance by 1oC or 1 K?
a)
specific heat
b)
heat energy
c)
enthalpy of formation
d)
heat capacity
14.
When 41.5 g of an alloy, at 24.6oC, are dropped into 100.0 g of water, the alloy absorbs 954 J of heat. If the final temperature of the allow is 39.2oC, what is its specific heat?
a)
1010 J/g⋅K
b)
0.595 J/g⋅K
c)
336 J/g⋅K
d)
1.57 J/g⋅K
15.
On what principle does calorimetry depend?
a)
law of conservation of energy
b)
law of enthalpy
c)
Hess's Law
d)
law of multiple proportions
16.
In a calorimeter, the energy content of a substance is calculated from measurement of the temperature change in a known mass of
a)
steel
b)
air
c)
iron
d)
water
17.
The specific heat of mercury is 0.140 J/g⋅K. How many joules of energy are needed to warm 4.52 g of mercury from 24.6 oC to 27.1 oC?
a)
0.632 J
b)
13.8 J
c)
3.96 J
d)
1.58 J
18.
Energy is measured in units of
a)
kelvin
b)
grams
c)
pounds
d)
joules
19.
To determine the amount of energy as heat associated with the change taking place in a calorimeter, the information that is not needed is the
a)
specific heat of the calorimeter
b)
specific heat of the water
c)
change in temperature of the water
d)
air temperature outside the calorimeter.
20.
The energy transferred between samples of matter because of a difference in their temperatures is called
a)
temperature
b)
thermochemistry
c)
heat
d)
chemical kinetics
21.
The quantity of energy transferred as heat during a temperature change between two species depends on the
a)
mass of the two materials involved in the temperature change.
b)
nature of the two materials involved in the temperature change.
c)
magnitude of the temperature change.
d)
All of the above.
22.
What units are used to measure specific heat?
a)
cal/g⋅K
b)
J/g⋅oC
c)
J/g⋅K
d)
all of these
23.
How much energy is absorbed as heat by 18.7 g gold when it is heated from 28.2oC to 31.8oC? The specific heat of gold is 0.13 J/g⋅K.
a)
0.675 J/g⋅K
b)
8.8 J
c)
8.8 J/g⋅K
d)
0.675 J
24.
How much energy does a copper sample absorb as energy in the form of heat if its specific heat is 0.384 J/g⋅K, its mass is 8.53 g, and it is heated from 11.3 oC to 44.7 oC?
a)
135 J/g⋅K
b)
285 J
c)
109.4 J/g⋅K
d)
109.4 J
25.
How is a Celsius temperature converted to a Kelvin temperature reading?
a)
by dividing by 273.15.
b)
by subtracting 273.15
c)
by adding 273.15
d)
by multiplying by 273.15
26.
The Greek letter Δ stands for
a)
"heat stored in"
b)
"rate of"
c)
"change in"
d)
"mass of"
27.
What is the mass of a sample that absorbs 50.2 J of energy when it is heated from 274 K to 360 K and has a specific heat of 0.292 J/g⋅K?
a)
2.00 g
b)
14785 g
c)
-0.297 g
d)
2.00 kg
28.
ΔH =
a)
Hproducts × Hreactants
b)
Hreactants − Hproducts
c)
Hproducts − Hreactants
d)
Hproducts + Hreactants
29.
The q in thermodynamic equations is
a)
temperature
b)
mass
c)
specific heat
d)
energy lost or gained
30.
A 4.5 g sample of metal was heated from 8.4 oC to 22.4 oC. It absorbed 41.9 J of energy as heat. What is the specific heat of this material?
a)
0.453 J/g⋅K
b)
130 J/g⋅K
c)
1.50 J/g⋅K
d)
0.665 J/g⋅K
31.
When your body breaks down sugar completely, how much heat is released compared to burning the same amount of sugar in a flame?
a)
The body released more heat.
b)
The body releases no heat.
c)
The body releases less heat.
d)
The body releases the same amount of heat.
32.
A chemical reaction is exothermic when ΔH is
a)
constant
b)
positive
c)
zero
d)
negative
33.
Find the specific heat of a material is a 9.98 g sample absorbs 55.4 J when it is heated from 33.9 oC to 53.1 oC.
a)
107 J
b)
-0.289 J/g⋅K
c)
0.289 J/g⋅K
d)
28.8 J
34.
The term thermodynamics refers to the study of
a)
only chemical changes.
b)
energy changes.
c)
only physical changes.
d)
none of these.
35.
A 7.97 g sample of silver is heated from -6.9 oC to 31.7 oC and absorbs 73.9 J of energy as heat. What is the specific heat of silver?
a)
0.74 J(g⋅oC)
b)
0.24 J
c)
0.74 J
d)
0.24 J/g⋅K
100 %
