WorksheetsCalorimetry
Total questions: 20
Worksheet time: 41mins
Name
Class
Date
1.
For the formula:
Q= m c ∆T
The units for specific heat are:
Q= m c ∆T
The units for specific heat are:
a)
g /J °C
b)
°C/g J
c)
kJ/g
d)
J/g°C
2.
What would be the effect on the particles if more heat is supplied to the system?
a)
They would slow down
b)
They would stop moving
c)
They would speed up
d)
There would be no effect
3.
If two objects have different temperatures, heat will flow from the warmer object to the cooler one UNTIL ____________
a)
one reaches a temperature of zero
b)
they both have an equal temperature
c)
one runs out of energy
4.
The total energy of all the particles in a substance is called:
a)
temperature
b)
thermal energy
c)
degrees
d)
mass
5.
If the specific heat of water is 4.18 J/g∙°C, how much heat is required to increase the temperature of 1.2 kg of water from 23 °C to 39 °C? (show your work)
a)
-80,256
b)
80.256
c)
80,256
d)
-80.256
6.
What is the specific heat of an unknown substance if 100.0 g of it at 200.0 °C reaches an equilibrium temperature of 27.1 °C when it comes in contact with a calorimeter of water? The water weighs 75. g and had an initial temperature of 20.00 °C.
(Specific heat of water is 4.18 J/g°C).
(Specific heat of water is 4.18 J/g°C).
a)
0.111 J/g°C
b)
1.29 J/g°C
c)
0.129 J/g°C
d)
22225.85 J
7.
For a skillet, used for cooking, do you want a high or low specific heat?
a)
High, so that it will need more energy to heat up
b)
Low, so that it will change temperature quickly
8.
The SI unit of heat and energy is the __________.
a)
calorie
b)
heat
c)
joule
d)
watt
9.
A sample of iron receives 50.J of heat energy that raises the temperature of the iron by 25.0°C. If iron has a specific heat of 0.10 J/g°C, what is the mass of the iron sample? (show your work)
a)
25g
b)
30g
c)
20g
d)
50g
10.
A reaction is performed in a beaker with a temperature probe recording the temperature changes of the reaction. If the temperature began at 15.0 degrees Celsius and ended at 27.5 degrees Celsius. Is the reaction endothermic or exothermic?
a)
Exothermic
b)
Endothermic
11.
A piece of metal with a mass of 32.8 g is heated to 100.5°C and dropped into 138.2 g of water at 20.0°C. The final temperature of the system is 30.2°C. What is the specific heat capacity of the metal? (show your work)
a)
2.56 J/g°C
b)
0.391 J/g°C
c)
5.29 J/g°C
d)
3.50 J/g°C
12.
In an exothermic process, the surroundings are gaining energy.
a)
True
b)
False
13.
If you were to hold an endothermic reaction in your hand, your hand would get colder because the reaction is gaining heat energy from your hand.
a)
True
b)
False
14.
Water molecules have the greatest kinetic energy in
________________
________________
a)
Ice at 0 °C.
b)
Water at 373 K.
c)
Water at 98 °C
d)
Steam at 150 °C.
15.
A metal cube at temperature of 10°C immersed in a liquid at temperature of 70°C.
What is the temperature of the metal cube when thermal equilibrium is achieved between the cube and the liquid?
What is the temperature of the metal cube when thermal equilibrium is achieved between the cube and the liquid?
a)
Between 10°C and 70°C
b)
More than 70°C
c)
Less than 10°C
d)
Same as the room temperature
16.
Nitrogen reacts with hydrogen to produce ammonia according to the following equation:
N2(g)+3H2(g)→2NH3(g); ΔH=-92 kJ mol-1
The energy change for this reaction is best described as
N2(g)+3H2(g)→2NH3(g); ΔH=-92 kJ mol-1
The energy change for this reaction is best described as
a)
exothermic, because the net strength of the bonds in the products is greater than the net strength of the bonds in the reactants
b)
endothermic, because the net strength of the bonds in the products is greater than the net strength of the bonds in the reactants
c)
exothermic, because the net strength of the bonds in the products is less than the net strength of the bonds in the reactants
d)
endothermic, because the net strength of the bonds in the products is less than the net strength of the bonds in the reactants
17.
A 2.200 g sample of quinone (C6H4O2) is burned in a bomb calorimeter whose total heat capacity is 7.854 kJ/°C. The temperature of the calorimeter increases from 23.44°C to 30.57°C. What is the heat of combustion per mole of quinone?
a)
-2700 kJ/mol
b)
-56.0 kJ/mol
c)
0.0204 kJ/mol
d)
-25.5 kJ/g
18.
Which of the following correctly states the energy changes occurring when chemical bonds are formed and broken?
a)
Energy is released when bonds are formed and when they are broken.
b)
Energy is absorbed when bonds are formed and when they are broken.
c)
Energy is absorbed when bonds are formed and released when they are broken.
d)
Energy is released when bonds are formed and absorbed when they are broken.
19.
A solution calorimeter is used in two experiments to examine the endothermic reaction of ammonium nitrate with water. In the first experiment 10.0 g of NH4NO3 was added to 100.0 mL of water at 25°C in the calorimeter. In the second experiment 100.0 g of NH4NO3 was added to 100.0 mL of water at 25°C. The temperature of the second experiment compared with the first will
a)
Fall at the same rate to the same temperature
b)
Fall at the same rate to a lower temperature
c)
Fall at the faster rate to the same temperature
d)
Fall at the faster rate to a lower temperature
20.
Humans obtain all of their energy requirements from the food they eat. The amount of energy in food can be measured using a bomb calorimeter. The following are steps, in random order, that are taken to determine experimentally the energy content of a sample of a food, using a bomb calorimeter.
1. Measure the rise in temperature.
2. Fill the calorimeter with water and wait until the temperature has reached a steady value.
3. Accurately weigh the sample of the food and place it inside the sealed compartment or 'bomb' in the presence of excess oxygen.
4. Measure the rise in temperature again.
5. Pass a measured amount of electrical energy into the system.
6. Ignite the sample with electrical ignition wires.
Which one of the following alternatives best presents an appropriate sequence of procedures?
1. Measure the rise in temperature.
2. Fill the calorimeter with water and wait until the temperature has reached a steady value.
3. Accurately weigh the sample of the food and place it inside the sealed compartment or 'bomb' in the presence of excess oxygen.
4. Measure the rise in temperature again.
5. Pass a measured amount of electrical energy into the system.
6. Ignite the sample with electrical ignition wires.
Which one of the following alternatives best presents an appropriate sequence of procedures?
a)
5, 1, 3, 2, 4, 6
b)
2, 3, 1, 5, 6, 4
c)
3, 2, 5, 1, 6, 4
d)
3, 6, 1, 2, 5, 4
100 %
