Sem 2- (6 week 2) Flashcards
(126 cards)
1
Q
What type of energy is associated with movement?
Kinetic
Potential
A
Kinetic
2
Q
What type of energy is stored energy?
Kinetic
Potential
A
Potential
3
Q
What type of energy is heat energy?
Thermal
Chemical
A
Thermal
4
Q
What type of energy is the energy found in the bonds of molecules?
Thermal
Chemical
A
Chemical
5
Q
A rock is perched upon a cliff. It has \_\_\_\_\_\_\_\_\_\_ energy. Kinetic Potential Thermal Chemical
A
Potential
6
Q
Energy associated with the movement is classified as ___________ energy.
Kinetic
Potential
A
Kinetic
7
Q
A hot pack gets hot after the molecules inside the container react. Based only on the information provided, what energy changes are occuring? Chemical to Thermal Thermal to Chemical Thermal to Potential Kinetic to Thermal
A
Chemical to Thermal
8
Q
Energy that is located within the bonds of a molecule is classified as __________ energy.
Thermal
Chemical
A
Chemical
9
Q
An Olympic high diver stands on the edge of a diving board before gracefully diving into the water. Based only on the information provided, what two forms of energy are present in this example? Thermal and Chemical Potential and Kinetic Thermal and Potential Kinetic and Chemical
A
Potential and Kinetic
10
Q
Which type of energy is correctly paired with its description?
Kinetic: associated with stored energy
Potential: associated with movement of molecules
Thermal: energy found in the bonds between atoms
Chemical: energy found in the bonds between atoms
A
Chemical: energy found in the bonds between atoms
11
Q
Energy can be destroyed
True
False
A
False
12
Q
A rock rolling down a hill involves the transfer of potential energy into kinetic energy.
True
False
A
True
13
Q
A hand warmer consists of two layers. The inner layer contains two chemicals separated by a thin plastic coating. The outer layer is thicker, and protects users from exposure to chemicals. What two types of energy are seen if the inner plastic layer is broken, allowing the chemicals to mix and produce heat?
Chemical and Thermal
Thermal and Kinetic
Chemical and Potential
A
Chemical and Thermal
14
Q
Energy can be transferred from one substance to another?
True
False
A
True
15
Q
A cup of hot chocolate becomes cold when it loses its energy after sitting out too long. What type of energy is being described?
Potential Energy
Chemical Energy
Thermal Energy
A
Thermal Energy
16
Q
Which of the following is true for the 1st law of thermodynamics;
Energy can be created
Energy can be transferred
Energy comes in many forms, but must stay in that form
Energy can be destroyed
A
Energy can be transferred
17
Q
Spatulas are a cooking utensil used for flipping food as it cooks and they can be made out of many different materials. Using the following information about various spatula materials, which material would you prefer to cook with?
Substance that the spatula is made of
Characteristics of that substance
Iron
Holds thermal energy, does not bend when exposed to kinetic energy
Wood
Does not hold thermal energy, does not bend when exposed to kinetic energy
Aluminum
Holds thermal energy, Bends when exposed to kinetic energy
Paper
Does not hold thermal energy, bends when exposed to kinetic energy
Iron
Wood
Aluminum
Paper
A
Wood
18
Q
A piece of zinc is placed over a Bunsen burner until it starts to melt. While still mostly solid, the zinc is dropped into a beaker of cool water. Which of the following is true about this experiment:
The cold energy from the water will transfer into the metal
The metal will continue to get warmer because of the added energy of the water .
The metal will transfer energy to the water, making the water get warmer.
The metal will transfer energy to the water, making the water get colder.
A
The metal will transfer energy to the water, making the water get warmer.
19
Q
Stored energy is also classified as \_\_\_\_\_\_\_\_\_\_\_\_\_ energy. Thermal Energy Chemical Energy Kinetic Energy Potential Energy
A
Potential Energy
20
Q
According to the first law of thermodynamics, energy cannot be \_\_\_\_\_\_\_ or \_\_\_\_\_\_\_. But it can be \_\_\_\_\_\_\_\_\_\_\_\_. created, transferred, conserved destroyed, transferred, created created, destroyed, transferred destroyed, transferred, conserved
A
created, destroyed, transferred
21
Q
Which of the following is true for the 1st law of thermodynamics;
Energy can be created
Energy comes in many forms, but must stay in that form
Energy can be transferred
Energy can be destroyed
A
Energy can be transferred
22
Q
Stored energy is classified as \_\_\_\_\_\_\_\_\_\_\_ energy. Chemical Thermal Kinetic Potential
A
Potential
23
Q
Cooking pots are used to transfer heat to food and cook it and they can be made of many different materials. Using the following information about various pots, which material would you choose for a pot?
Substance that the pot is made of
Characteristics of that substance
Iron
Holds thermal energy, does not react when chemical changes occur inside of it
Wood
Does not hold thermal energy, does not react when chemical changes occur inside of it
Aluminum
Holds thermal energy, reacts when chemical changes occur inside of it
Paper
Does not hold thermal energy, reacts when chemical changes occur inside of it Iron Wood Aluminum Paper
A
Iron
24
Q
A hand warmer gets warm after the molecules inside the container combine. Based only on the information provided, which of the following shows the energy change? chemical to thermal kinetic to potential thermal to potential kinetic to thermal
A
chemical to thermal
25
A cold piece of iron is placed inside of an empty bowl. Boiling water is poured on top of the iron. Which of the following is true about this experiment:
The cold energy from the water will transfer into the metal
The metal will get warmer because the water will add energy to it.
The metal will transfer energy to the water, making the water get warmer.
The metal will transfer energy to the water, making the water get colder.
The metal will get warmer because the water will add energy to it.
26
```
Energy that is located within the bonds of a molecule is classified as __________ energy.
Thermal
Kinetic
Gravitational
Chemical
```
Chemical
27
```
Energy associated with movement is also classified as _____________ energy.
Gravitational energy
Chemical energy
Kinetic energy
Potential energy
```
Kinetic energy
28
```
A race car gets slightly bumped by another driver during a NASCAR race. This causes the race car that was bumped to slam into the wall. Based only on the information provided, what two forms of energy are present in this example?
Thermal and Chemical
Potential and Kinetic
Thermal and Potential
Kinetic and Chemical
```
Potential and Kinetic
29
```
According to the first law of thermodynamics, energy cannot be _______ or _______. But it can be ____________.
destroyed, transferred, created
created, transferred, conserved
destroyed, transferred, conserved
created, destroyed, transferred
```
created, destroyed, transferred
30
Which type of energy is correctly paired with its description?
Chemical: energy found in the bonds between atoms
Thermal: energy found in the bonds between atoms
Kinetic: associated with stored energy
Potential: associated with movement of molecules
Chemical: energy found in the bonds between atoms
31
Temperature measures heat
True
False
False
32
Which part of a reaction has more energy for an exothermic reaction?
Products
Reactants
Reactants
33
A thermometer works by directly measuring the amount of heat energy around it.
True
False
False
34
You light a campfire to cook s’mores. The system for this reaction is ___________, and the surroundings are ___________.
the smoke above the fire; the logs burning on the fire
the logs burning on the fire; the ashes
the logs burning on the fire; everything outside of the fire
everything outside of the fire; the logs burning on the fire
the logs burning on the fire; everything outside of the fire
35
Which part of a reaction has more energy for an endothermic reaction?
Products
Reactants
Products
36
Which of the statements below are true regarding systems and surroundings?
A system is where the reaction occurs, while the surroundings are where the reaction came from
Surroundings include the reaction itself
A system is where the reaction occurs, while the surroundings are everything outside of that reaction
A system is outside of the reaction itself
A system is where the reaction occurs, while the surroundings are everything outside of that reaction
37
An ice cube melts on your hand. This is an example of an ______________ reaction.
Endothermic
Exothermic
Endothermic
38
A campfire is an example of an _____________ reaction.
Endothermic
Exothermic
Exothermic
39
```
A sample of salt is placed within a Styrofoam cup filled with water. The salt dissolves rapidly. The water inside the cup gets colder, while the cup stays the same temperature. The salt is the _______, while the water is the ___________.
system, system
surroundings, system
system, surroundings
surroundings, surroundings
```
system, surroundings
40
```
Liquid water is placed into a freezer. Heat transfers from the __________ to the ________, resulting in an ___________ process.
freezer, water, exothermic
water, freezer, endothermic
freezer, water, endothermic
water, freezer, exothermic
```
water, freezer, exothermic
41
The initial temperature of water is 15.0 °C, and the final temperature is 23.0 °C. What is the change in temperature of the water?
8. 0 °C
- 8.0 °C
38. 0 °C
- 38.0 °C
8.0 °C
42
A reaction’s reactants possess 400.0 kJ of energy, and its products possess 200.0 kJ of energy. What type of reaction is this?
Exothermic
Endothermic
Exothermic
43
```
A reaction heats up 50.0 grams of water from 22.0 °C, to 28.0 °C. Water has a specific heat of 4.184. How much energy was released?
-1260 J
10,500 J
1260 J
-10,500 J
```
1260 J
44
Molecule
ΔH (kJ/mol)
H2O
-285.82
H2 (g)
0
O2 (g)
0
2H2O --> 2H2 + O2
Calculate the enthalpy for the equation above.
- 285.82 kJ/mol
285. 82 kJ/mol
- 571.64 kJ/mol
571. 64 kJ/mol
571.64 kJ/mol
45
A reaction gives an enthalpy (ΔH) value of -1283.0 kJ/mol. This reaction is;
Endothermic
Exothermic
Exothermic
46
Find the statement below that would be true about the following equation;
CH4 + O2 CO2 + H2O + 785 kJ/mol
The reaction is exothermic, The reaction is gaining energy
The reaction is endothermic, The reaction is gaining energy
The reaction is exothermic, The reaction is losing energy
The reaction is endothermic, The reaction is losing energy
The reaction is exothermic, The reaction is losing energy
47
Before a chemical reaction begins, reactants of a chemical equation have 550.0 kJ of energy. After the reaction has completed, the products now have 300.0 kJ of energy. Which of the following is true about this reaction?
The reaction is exothermic, -250.0 kJ of energy were released, the enthalpy value for this reaction is negative
The reaction is endothermic, - 250.0 kJ of energy were released, the enthalpy value for this reaction is negative
The reaction is exothermic, 250.0 kJ of energy were absorbed, the enthalpy value for this reaction is positive
The reaction is endothermic, 250.0 kJ of energy were absorbed, the enthalpy value for this reaction is positive.
The reaction is exothermic, -250.0 kJ of energy were released, the enthalpy value for this reaction is negative
48
Molecule
ΔH (kJ/mol)
H2O2 (g)
-136.31
H2O (l)
-285.82
O2
0
2 H2O2 2H2O + O2
Using the information available in the chart above, solve for the energy change in the equation provided. After solving for the energy value, label the equation as being exothermic or endothermic.
299. 02 kJ/mol
- 299.02 kJ/mol
- 149.51 kJ/mol
149. 51 kJ/mol
-299.02 kJ/mol
49
```
An unknown mass of water is heated from 24.0 °C to 35.0 °C. Water has a specific heat capacity of 4.184. If 353 J are absorbed by the water during the heating, what is the mass of the water?
7.67 mL of water
16,200 mL of water
3.52 mL of water
0.13 mL of water
```
7.67 mL of water
50
An unknown sample with a mass of 5.66 grams gains 28.0 J of energy, and has a temperature change of 11.0 °C. What is the identity of the unknown sample?
Sample
Specific heat values
Aluminum
0.90
Lead
0.13
Iron
0.45
Water
4.184
Aluminum
Lead
Water
Iron
Iron
51
The initial temperature of water is 30.0 °C, and the final temperature is 25.0 °C. What is the change in temperature of the water.
5. 0 °C
- 5.0 °C
55. 0 °C
- 55.0 °C
-5.0 °C
52
```
A reaction’s reactants possess 200.0 kJ of energy, and its products possess 250.0 kJ of energy. What type of reaction is this?
Exothermic
Endothermic
Potential
Kinetic
```
Endothermic
53
Find the statement below that would be true about the following equation;
571.64 + 2H2O 2H2 + O2
The reaction is exothermic, The reaction is gaining energy
The reaction is endothermic, The reaction is losing energy
The reaction is endothermic, The reaction is gaining energy
The reaction is exothermic, The reaction is losing energy
The reaction is endothermic, The reaction is gaining energy
54
Before a chemical reaction begins, reactants of a chemical equation have 200.0 kJ of energy. After the reaction has completed, the products now have 450.0 kJ of energy. Which of the following is true about this reaction?
The reaction is exothermic, -250.0 kJ of energy were released, the enthalpy value for this reaction is negative
The reaction is endothermic, - 250.0 kJ of energy were released, the enthalpy value for this reaction is negative
The reaction is exothermic, 250.0 kJ of energy were absorbed, the enthalpy value for this reaction is positive
The reaction is endothermic, 250.0 kJ of energy were absorbed, the enthalpy value for this reaction is positive.
The reaction is endothermic, 250.0 kJ of energy were absorbed, the enthalpy value for this reaction is positive.
55
An unknown sample with a mass of 2.59 grams gains 28.0 J of energy, and has a temperature change of 12.0 °C. What is the identity of the unknown sample?
Sample
Specific heat values
Aluminum
0.90
Lead
0.13
Iron
0.45
Water
4.184
Aluminum
Lead
Water
Iron
Aluminum
56
ΔH is measured in J/mole
True
False
False
57
Which of the following is false regarding the process of determining ΔH using Calorimetry.
Specific heat is dependent upon the substance that absorbs the energy from the reaction.
To find temperature simply subtract Final – Initial
To convert J into kJ multiply by 1000
Moles are determined using the grams of the substance that was actually burned, or reacted
To convert J into kJ multiply by 1000
58
Convert 22.3 grams of CH4 into moles of CH4.
0. 717 moles
1. 86 moles
1. 39 moles
1. 00 moles
1.39 moles
59
```
Convert 7593 J into kJ.
7593000
0.7593
75.93
7.593
```
7.593
60
```
Energy from a reaction was determined to be 11563 J, when burning 15.0 grams of H2. What is the total enthalpy of the reaction?
771 kJ/mole
-1.54 kJ/mole
1540 kJ/mole
0.649 kJ/mole
```
-1.54 kJ/mole
61
A 2.50 gram sample of CH4 is burned in a calorimeter. The calorimeter is filled with 100.0 grams of water. The temperature of a calorimeter increases from 20.0°C to 30.0 C. Calculate the energy lost or gained by the reaction in kJ per mole.
- 26.8 kJ/mole
26. 8 kJ/mole
0. 0373 kJ/mole
- 1.67 kJ/mole
-26.8 kJ/mole
62
```
A calorimeter is used to measure the combustion of 14.0 grams of H2 gas under 150. grams of water. The energy measured using the water was 10,432 J. What is the heat lost or gained by the total reaction?
1490 kJ/mol
-0.745 kJ/mol
-1.49 kJ/mol
745 kJ/mol
```
-1.49 kJ/mol
63
Convert 22.1 grams of CO2 into moles.
0. 500 moles
1. 99 moles
0. 790 moles
1. 23 moles
0.500 moles
64
```
A calorimeter is used to measure the combustion of 8.00 grams of H2 gas under 75.0 grams of water. The energy measured using the water was 15,400 J. What is the heat lost or gained by the total reaction?
-3850 kJ/mol
1930 kJ/mol
-1.93 kJ/mol
-3.85 kJ/mol
```
-3.85 kJ/mol
65
ΔH is measured in kJ/mol
True
False
True
66
Which of the following is true regarding the process of determining ΔH using Calorimetry?
All substances have the same specific heat capacity
To find temperature simply subtract Initial – Final
To convert J into kJ divide by 1000
In the process of Calorimetry, moles are determined using the grams of the substance that absorbed the energy from the reaction
To convert J into kJ divide by 1000
67
Which type of energy is correctly paired with its description?
Potential: associated with movement of molecules
Thermal: energy found in the bonds between atoms
Kinetic: associated with stored energy
Chemical: energy found in the bonds between atoms
Chemical: energy found in the bonds between atoms
68
Convert 28.1 grams of CO2 into moles.
1. 00 moles
1. 57 moles
0. 996 moles
0. 639 moles
0.639 moles
69
Before a chemical reaction begins, reactants of a chemical equation have 300.0 kJ of energy. After the reaction has completed, the products now have 550.0 kJ of energy. Which of the following is true about this reaction?
The reaction is endothermic, 250.0 kJ of energy were absorbed, the enthalpy value for this reaction is positive.
The reaction is endothermic, - 250.0 kJ of energy were released, the enthalpy value for this reaction is negative.
The reaction is exothermic, 250.0 kJ of energy were absorbed, the enthalpy value for this reaction is positive.
The reaction is exothermic, -250.0 kJ of energy were released, the enthalpy value for this reaction is negative.
The reaction is endothermic, 250.0 kJ of energy were absorbed, the enthalpy value for this reaction is positive.
70
```
A pool player uses the cue stick to strike the cue ball sending it down the pool table. The cue ball gently hits the eight ball, sending it into a nearby pocket. Based only on the information provided, what two forms of energy are present in this example?
Thermal and Chemical
Potential and Kinetic
Thermal and Potential
Kinetic and Chemical
```
Potential and Kinetic
71
```
According to the first law of thermodynamics, energy cannot be _______ or _______. But it can be ____________.
destroyed, transferred, created
created, transferred, conserved
destroyed, transferred, conserved
created, destroyed, transferred
```
created, destroyed, transferred
72
Gas particles are almost always in motion, and stop only when they collide with the walls of their container.
True
False
False
73
The distances between gas particles could be considered great when compared to the size of the particles themselves.
True
False
True
74
Gas pressure is caused by the temperature and size of gas particles.
True
False
False
75
Gas molecules exert no attractive or repulsive forces on each other or the container walls; therefore, their collisions are ________________.
elastic
76
```
Gas particles have kinetic energy that is ______________ proportional to their Kelvin temperature.
Inversely
Directly
Oppositionally
Increasingly
```
Directly
77
```
As the temperature of gas molecules is decreased, their kinetic energy, and therefore the pressure exerted by the molecules, _________________.
stays the same
is increased
is decreased
is doubled
```
is decreased
78
```
Temperature is the intensity of _____________ present in a substance.
pressure
heat
light
molecules
```
heat
79
The amount of a gas is counted in _____________.
moles
80
The values chemists use for standard temperature and pressure are [ Select ] degrees Kelvin and [ Select ] atm.
273 ; 1
81
In order to convert a temperature from degrees Celsius to degrees Kelvin, one must add _____ to the Celsius temperature.
273
82
The amount of three-dimensional space a gas occupies is its _______________.
volume
83
```
If the volume a gas occupies is decreased while the temperature and amount are held constant, what will happen to the pressure that gas exerts?
It will increase
It will decrease
It will stay the same
No answer text provided.
```
It will increase
84
```
If the temperature of a gas is decreased while the amount is held constant, what will happen to the volume of the gas?
It will increase
It will decrease
It will stay the same
No answer text provided.
```
It will decrease
85
```
If the number of moles of a gas is increased while the temperature is held constant, what will happen to its volume?
It will increase
It will decrease
It will stay the same
No answer text provided.
```
It will increase
86
```
If a can with a volume of 500ml is filled with gas at a temperature of 25° Celcius, and the can is sealed so that the amount of gas in the can cannot change, what will happen to the pressure in the can if you put it in the freezer?
It will increase
It will decrease
It will stay the same
No answer text provided.
```
It will decrease
87
```
If a hot air balloon is filled with 78,000 moles of gas and then that gas is heated from 293 degrees Kelvin to 380 degrees Kelvin with a propane flame, what will happen to the volume of the balloon?
It will increase
It will decrease
It will stay the same
No answer text provided.
```
It will increase
88
```
What is the freezing point of water in degrees Kelvin?
0 Kelvin
100 Kelvin
273 Kelvin
373 Kelvin
```
273 Kelvin
89
```
If the temperature of a gas is decreased by half while the volume and amount are held constant, what will happen to the pressure that gas exerts?
The pressure is doubled
The pressure is halved
The pressure is quadrupled
The pressure remains the same
```
The pressure is halved
90
```
If the number of moles of a gas is doubled while the temperature and pressure is held constant, what will happen to its volume?
The volume is doubled
The volume is halved
The volume is quadrupled
The volume remains the same
```
The volume is doubled
91
```
If the volume of a gas is decreased by half while the number of moles is also decreased by half, what will happen to the pressure of the gas?
The pressure is doubled
The pressure is halved
The pressure is quadrupled
The pressure remains the same
```
The pressure remains the same
92
```
If the temperature of a gas is increased four times while the pressure and number of moles are held constant, what will happen to the volume of that gas?
The volume is doubled
The volume is halved
The volume is quadrupled
The volume remains the same
```
The volume is quadrupled
93
```
If a football is filled indoors with 4236 mL of air at a temperature of 25° Celsius, what will happen to the volume of the football if you take it outside on a winter day with an ambient air temperature of 2° Celsius?
It will increase
It will decrease
It will stay the same
It will explode
```
It will decrease
94
```
If a tire with a volume of 860 mL is filled with air at a temperature of 25° Celsius, what will happen to the pressure in the tire if the temperature is doubled?
The pressure is doubled
The pressure is halved
The pressure is quadrupled
The pressure remains the same
```
The pressure is doubled
95
If an engine cylinder contains 90 mL of gas at a temperature of 30° Celsius and a pressure of 1 atm. That volume is then compressed to 30 mL. If the pressure remains the same, what will happen to the temperature of the gas in the cylinder?
The temperature will decrease by a factor of two.
The temperature will increase by a factor of two.
The temperature will decrease by a factor of three.
The temperature will increase by a factor of four.
The temperature will decrease by a factor of three.
96
Which statement is true according to Kinetic Molecular Theory?
The distance between gas particles is small when compared to the size of those particles.
The force of attraction between molecules is high.
Gas particles transfer energy through collisions.
Gas particles are always stationary.
Gas particles transfer energy through collisions.
97
A sample of nitrogen, N2, occupies 45.0 mL at 27 °C and 600 torr. What pressure will it have in torr if cooled to –73 °C while the volume remains constant?
400 torr. The temperature of the gas has decreased, so we expect to see a corresponding decrease in pressure. Converting the Celsius temperatures to Kelvin (by adding 273 to each of them), cross multiplying P1 with T2, and then dividing the answer by T1 yields a P2 of 400 torr.
98
A sample of oxygen, O2, occupies 32.2 mL at 30 °C and 452 torr. What volume will it occupy at –70 °C and the same pressure?
21.6 mL. The temperature of the gas has decreased, so we expect to see a corresponding decrease in volume. Using Charles’ equation, we first convert the Celsius temperatures to Kelvin (by adding 273 to each of them), cross multiplying V1with T2, and then dividing the answer by T1 yields a V2 of 21.6 mL.
99
What is the volume in mL of a sample of ethane at 467 K and 1.1 atm if it occupies 405 mL at 298 K and 1.1 atm?
Using Charles’ law, we substitute 405 mL for V1, 298 K for T1, and 467 K for T2, and we leave V2 as the unknown volume. Cross-multiplying 405 x 467 and dividing the result by 298 yields a final volume of 635 mL. This result agrees with the expected increase in gaseous volume that should correspond to an increase in temperature. Answer is 635 mL.
100
Nitrogen gas is held in container of 3.6 liters at 910 mmHg. If we want to change the pressure to an atmospheric pressure of 760 mmHg, we would need a container with what volume in L? (Assume that temperature and number of moles remain constant.)
The problem gives us P1= 900 mmHg, V1 = 3.6 L, and P2 = 760 mmHg. We can plug these numbers into Boyle's equation to solve for V2, multiplying 3.6 L x 900 mmHg and dividing the result by 760 mmHg results in a final volume of 4.3 L.
101
A 30-cm balloon is held at a constant temperature and pressure, and contains 29.4 moles of gas and occupies 14 L of space. If 17.9 moles of gas are released from the balloon, what will be its new volume in L?
Using Avogadro’s equation, we substitute 14 L for V1, 29.4 moles for n1, and we subtract 17.9 n from 29.4 n to find that we have 11.5 moles for n2, and we leave V2 as our unknown variable. Cross-multiplying 14 x 11.5 and dividing the result by 29.4 yields a final volume of 5.5 L.
102
A tank holding 4.00 moles of helium gas at 77.0 °C has a pressure of 4.20 atm. How big is the tank in liters?
The problem gives you n = 4.00 moles, P= 4.2 atm, and T= 77 + 273 = 350 K. R is 0.0821 L x atm/mol x K. Plugging into the Ideal gas equation, we get:
(4.2 atm) x (V) = (4.00) x (0.0821 L x atm/mol x K) x (350 K)
which we can solve to find a volume of 27.4 L.
103
A pocket of hydrogen gas near the surface of a dwarf star flashes into existence for a moment, and contains 17530 moles of gas at a pressure of 2832 atm and a volume of 2200. L. What is the temperature of the gas pocket in Kelvin?
The problem gives you P= 2832 atm, V = 2200 L, and n = 17530 moles. R is 0.0821 L x atm/mol x K. Plugging into the Ideal gas equation, we get:
(2832 atm) x (2200 L) = (17530 mol) x (0.0821 L x atm/mol x K) x (T)
which we can solve to find a temperature of 4329 K.
104
How many moles of gaseous boron trifluoride, BF3, are contained in a 4.3410-L bulb at 788 K if the pressure is 1.22 atm?
Using the Ideal gas law, P = 1.22 atm, V = 4.341 L, R = 0.0821 L x atm/mol x K, T = 788 K, and n is our unknown. Plugging into the Ideal gas equation, we get:
(1.22 atm) x (4.341 L) = (n) x (0.0821 L x atm/mol x K) x (788 K)
which we solve to find that the number of moles is 0.0819 mol, or 8.190 x 10–2 mol.
105
A 0.50-L container is filled with hydrogen gas at STP. Calculate the change in temperature in Kelvin when the container is crushed by the vacuum of space to 0.070 L and 20.0 atm.
Using the Combined gas law, we have P1 = 1 atm, V1 = 0.5 L, T1 = 273 K, and P2 = 20 atm, V2 = 0.07 L, and T2 is our unknown variable. Plugging into the equation, we get:
(1 atm) x (0.5 L) / (273 K) = (20 atm) x (0.07 L) / (T2)
which we solve to find that the final temperature is 764 K.
106
A cylinder of medical oxygen has a volume of 35.4 L, and contains O2 at a pressure of 151 atm and a temperature of 25.0 °C. What volume in L of O2 does this correspond to at normal body conditions, that is, 1.00 atm and 37.0 °C?
Using the Combined gas law, we have P1 = 151 atm, V1 = 35.4 L, T1 = 298 K, and P2 = 1 atm, T2 = 310 K, and V2 is our unknown variable. Plugging into the equation, we get:
(151 atm) x (35.4 L) / (298 K) = (1 atm) x (V2) / (310 K)
which we solve to find that the corresponding volume is 5561 L.
107
A balloon that is 100.21 L at 21.0 °C and 0.981 atm is released and just barely clears the top of Mount Crumpet in British Columbia. If the final volume of the balloon is 144.53 L at a temperature of 5.24 °C, what is the pressure in atm experienced by the balloon as it clears Mount Crumpet?
Using the Combined gas law, we have P1 = 0.981 atm, V1 = 100.21 L, T1 = 294 K, and V2 = 144.53 L, T2 = 278.24 K, and P2 is our unknown variable. Plugging into the equation, we get:
(0.981 atm) x (100.21 L) / (294 K) = (P2) x (144.53 L) / (278.24 K)
which we solve to find that the pressure experienced by the balloon is 0.644 atm.
108
```
How many moles of gas are held in a container with a volume of 780.0 mL at a temperature of 90.0 °C, and a pressure of 0.7105 atm?
57100 mol
53.7 mol
16.5 mol
0.0186 mol
```
0.0186 mol
109
```
A tank holding 72.4 moles of helium gas at 42.0 °C has a pressure of 1.0526 atm. How big is the tank in liters?
1780 L
2.34 L
1960 L
0.312 L
```
1780 L
110
```
A 24.4 L tank holds 56.8 moles of helium gas at 297 K. Calculate the pressure of the tank in atm.
33800 atm
56.7 atm
10.5 atm
0.0170 atm
```
56.7 atm
111
A 7583 mL tank holds 9.55 moles of helium gas at 0.9803 atm. Calculate the temperature of the gas in K.
9. 48 K
7. 92 K
6. 07 K
1. 93 K
9.48 K
112
```
A 433 L tank holds helium gas at -48.0 °C with a pressure of 939 torr. How many moles of gas are in the tank?
6450 mol
22100 mol
0.0340 mol
29.1 mol
```
29.1 mol
113
How many liters does 298.00 moles of N2O at STP represent?
298 moles can be converted to liters by using the conversion factor (22.4 L = 1 mol), which shows that the gas would occupy 6675.2 L, as would that amount of any gas at STP.
114
How many moles of Kr are there in 17 liters at STP?
17 L Kr is converted to moles by using the conversion factor (1 mol = 22.4 L). By multiplying 17 x 1 and dividing the result by 22.4, we find that the amount is 0.76 mol.
115
How many grams of NH3 are there in 7.43 liters at STP?
We first convert liters to moles using the conversion factor (1 mol = 22.4 L). By multiplying 7.43 x 1 and dividing by 22.4, we find that there are 0.33 moles present. We then find the molar mass of NH3 ((1 x 14) + (3 x 1) = 17 g/mol), and multiply (0.33 mol) x (17 g/mol) to find that there are 5.61 g of Kr in 7.43 L.
116
How many liters would be occupied by 7.71 g of F2 gas at STP?
We first find the molar mass of fluorine (F2), which is 19 x 2 = 38 g/mol. We can use this relationship to convert 7.71 grams to moles, multiplying 7.71 g x (1 mol/38 g) to find that there are 0.20 mol F2. We then use the conversion factor (22.4 L = 1 mol) to find the amount in liters, (0.20 mol x (22.4 L / 1 mol) = 4.48 L.
117
How many grams of ethane (C2H6) are there in 12,423 liters at STP?
We first convert liters to moles ((12,423 L) x (1 mol / 22.4 L) = 554.6 mol). We then use the molar mass of C2H6 (30 g/mol) to convert the amount to grams ((554.6 mol) x (30 g/mol) = 16638 g).
118
In the following reaction, what volume in L of oxygen (O2(g)) measured at STP is required to react with 26.7 L of ethylene (C2H4(g)) measured under the same conditions of temperature and pressure?
C2H4 (g) + 3O2 (g) ⟶ 2CO2 (g) + 2H2O (g)
From the equation, 3 volumes of O2 are required to react with each volume of C2H4, so we use this ratio to convert:
(26.7 L C2H2) x (3 L O2 / 1 L C2H2) = 80.1 L
119
In the following reaction, how many liters of CH4 are required to react with 1472 L O2 at STP?
CH4 (g) + 2O2 (g) ⟶ CO2 (g) + 2H2O (g)
From the equation, 1 volume of CH4 is required to react with every 2 volumes of O2, so we use this ratio to convert:
(1472 L O2) x (1 L CH4 / 2 L O2) = 736 L CH4
120
In the following reaction, how many liters of H2 would be produced if 42.0 g Mg were allowed to react completely at STP?
Mg (s) + 2 HCl (aq) ⟶ MgCl2 (aq) + H2 (g)
Convert grams of Mg to moles, then use the mole ratio from the equation to find the number of moles of H2 produced, and finally convert this amount to liters:
(42 g Mg) x (1 mol Mg / 24.305 g Mg) x (1 mol H2 / 1 mol Mg) x (22.4 L H2 / 1 mol H2) = 39.2 L H2
121
In the following reaction, how many liters of CO2 would be produced if 14.1 g O2 were allowed to react completely at STP?
C3H8 (g) + 5 O2 (g) ⟶ 3 CO2 (g) + 4 H2O (g)
Convert grams of O2 to moles, then use the mole ratio from the equation to find the number of moles of CO2 produced, and finally convert this amount to liters:
(14.1 g O2) x (1 mol O2 / 32 g O2) x (3 mol CO2 / 5 mol O2) x (22.4 L CO2 / 1 mol CO2) = 5.9 L CO2
122
In the following reaction, how many liters of water vapor would be produced if 122.9 g C3H8 were allowed to react completely at STP?
C3H8 (g) + 5 O2 (g) ⟶ 3 CO2 (g) + 4 H2O (g)
Convert grams of C3H8 to moles, then use the mole ratio from the equation to find the number of moles of H2O produced, and finally convert this amount to liters:
(122.9 g C3H8) x (1 mol C3H8 / 44.1 g C3H8) x (4 mol H2O / 1 mol C3H8) x (22.4 L C3H8 / 1 mol H2O) = 249.7 L H2O
123
For the following reaction, how many liters of oxygen (O2) gas are produced from the decomposition of 22.1 grams of mercuric oxide (HgO) at STP?
2 HgO (s) ⟶ 2 Hg (l) + O2 (g)
106. 85 L
4. 57 L
0. 01 L
1. 14 L
1.14 L
124
What volume of hydrogen gas at STP may be prepared by the reaction of 7.62 g gallium (Ga) with an excess of hydrochloric acid (HCl)? Use the following reaction to find your answer:
2 Ga (s) + 6 HCl (aq) ⟶ 2 GaCl3 (aq) + 3 H2 (g)
3. 67 L
14. 69 L
0. 03 L
7. 35 L
3.67 L
125
If 66.2 Liters of Carbon Monoxide gas react with excess Hydrogen, how many grams of methanol (CH3OH) can be made?
CO (g) + 2 H2 (g) ⟶ CH3OH (g)
46.3 g
47.4 g
189 g
94.7 g
94.7 g
126
What volume of nitric oxide (NO) can be produced from the complete reaction of 54.6 grams of ammonia (NH3) gas at STP?
4 NH3 (g) + 5 O2 (g) ⟶ 4 NO (g) + 6 H2O (g)
4. 5 L
71. 9 L
51. 4 L
0. 1 L
71.9 L
