Thermochemistry and Changes of State - AP Chemistry
Card 0 of 99
What is the definition of the triple point?
What is the definition of the triple point?
Definition of triple point: where solid, liquid, and gas exist in equilibrium
Definition of triple point: where solid, liquid, and gas exist in equilibrium
Compare your answer with the correct one above
What is represented by point D
What is represented by point D
the critical point is where the solid and gas cannot be distinguished
the critical point is where the solid and gas cannot be distinguished
Compare your answer with the correct one above
A solution of water is at 0.006atm and 0.01 degrees Celsius. What phase(s) are present in the sample?
A solution of water is at 0.006atm and 0.01 degrees Celsius. What phase(s) are present in the sample?
The point detailed in the question is the triple point of water on the phase diagram. At the triple point all three phases of a chemical coexist; as such the correct answer is solid, liquid, and gas.
The point detailed in the question is the triple point of water on the phase diagram. At the triple point all three phases of a chemical coexist; as such the correct answer is solid, liquid, and gas.
Compare your answer with the correct one above
What is the definition of the triple point?
What is the definition of the triple point?
Definition of triple point: where solid, liquid, and gas exist in equilibrium
Definition of triple point: where solid, liquid, and gas exist in equilibrium
Compare your answer with the correct one above
What is represented by point D
What is represented by point D
the critical point is where the solid and gas cannot be distinguished
the critical point is where the solid and gas cannot be distinguished
Compare your answer with the correct one above
A solution of water is at 0.006atm and 0.01 degrees Celsius. What phase(s) are present in the sample?
A solution of water is at 0.006atm and 0.01 degrees Celsius. What phase(s) are present in the sample?
The point detailed in the question is the triple point of water on the phase diagram. At the triple point all three phases of a chemical coexist; as such the correct answer is solid, liquid, and gas.
The point detailed in the question is the triple point of water on the phase diagram. At the triple point all three phases of a chemical coexist; as such the correct answer is solid, liquid, and gas.
Compare your answer with the correct one above
What is the definition of the triple point?
What is the definition of the triple point?
Definition of triple point: where solid, liquid, and gas exist in equilibrium
Definition of triple point: where solid, liquid, and gas exist in equilibrium
Compare your answer with the correct one above
What is represented by point D
What is represented by point D
the critical point is where the solid and gas cannot be distinguished
the critical point is where the solid and gas cannot be distinguished
Compare your answer with the correct one above
A solution of water is at 0.006atm and 0.01 degrees Celsius. What phase(s) are present in the sample?
A solution of water is at 0.006atm and 0.01 degrees Celsius. What phase(s) are present in the sample?
The point detailed in the question is the triple point of water on the phase diagram. At the triple point all three phases of a chemical coexist; as such the correct answer is solid, liquid, and gas.
The point detailed in the question is the triple point of water on the phase diagram. At the triple point all three phases of a chemical coexist; as such the correct answer is solid, liquid, and gas.
Compare your answer with the correct one above
What is the definition of the triple point?
What is the definition of the triple point?
Definition of triple point: where solid, liquid, and gas exist in equilibrium
Definition of triple point: where solid, liquid, and gas exist in equilibrium
Compare your answer with the correct one above
What is represented by point D
What is represented by point D
the critical point is where the solid and gas cannot be distinguished
the critical point is where the solid and gas cannot be distinguished
Compare your answer with the correct one above
A solution of water is at 0.006atm and 0.01 degrees Celsius. What phase(s) are present in the sample?
A solution of water is at 0.006atm and 0.01 degrees Celsius. What phase(s) are present in the sample?
The point detailed in the question is the triple point of water on the phase diagram. At the triple point all three phases of a chemical coexist; as such the correct answer is solid, liquid, and gas.
The point detailed in the question is the triple point of water on the phase diagram. At the triple point all three phases of a chemical coexist; as such the correct answer is solid, liquid, and gas.
Compare your answer with the correct one above
What is represented by point D
What is represented by point D
the critical point is where the solid and gas cannot be distinguished
the critical point is where the solid and gas cannot be distinguished
Compare your answer with the correct one above
What is the definition of the triple point?
What is the definition of the triple point?
Definition of triple point: where solid, liquid, and gas exist in equilibrium
Definition of triple point: where solid, liquid, and gas exist in equilibrium
Compare your answer with the correct one above
A solution of water is at 0.006atm and 0.01 degrees Celsius. What phase(s) are present in the sample?
A solution of water is at 0.006atm and 0.01 degrees Celsius. What phase(s) are present in the sample?
The point detailed in the question is the triple point of water on the phase diagram. At the triple point all three phases of a chemical coexist; as such the correct answer is solid, liquid, and gas.
The point detailed in the question is the triple point of water on the phase diagram. At the triple point all three phases of a chemical coexist; as such the correct answer is solid, liquid, and gas.
Compare your answer with the correct one above
As heat energy is added to a cube of ice, it begins to melt into liquid water. Which of the following correctly identifies the change in temperature and the change in internal energy of the ice as heat is added to it?
As heat energy is added to a cube of ice, it begins to melt into liquid water. Which of the following correctly identifies the change in temperature and the change in internal energy of the ice as heat is added to it?
Remember that when any substance is undergoing a phase change, its temperature will remain constant. In other words, the energy being added is not increasing the average kinetic energy of any of the particles in the system.
Also, the internal energy will not remain constant. As heat energy is added, as in the question, the internal energy will necessarily increase. Even though the kinetic energy of the particles is not increasing, the potential energy is. This is because the intermolecular forces of attraction (mostly hydrogen bonds in this case) need to be broken apart. When energy is added, that raises the potential energy component of internal energy, despite the fact that kinetic energy (and thus, temperature) remains constant.
Remember that when any substance is undergoing a phase change, its temperature will remain constant. In other words, the energy being added is not increasing the average kinetic energy of any of the particles in the system.
Also, the internal energy will not remain constant. As heat energy is added, as in the question, the internal energy will necessarily increase. Even though the kinetic energy of the particles is not increasing, the potential energy is. This is because the intermolecular forces of attraction (mostly hydrogen bonds in this case) need to be broken apart. When energy is added, that raises the potential energy component of internal energy, despite the fact that kinetic energy (and thus, temperature) remains constant.
Compare your answer with the correct one above
Which of the following is true of a closed system?
Which of the following is true of a closed system?
A closed system allows for the exchange of energy between the system and its surroundings, but does not allow the exchange of matter. This is the definition of a closed system. An open system allows for the exchange of both matter and energy between the system and its surroundings. An isolated system on the other hand does not allow the exchange of either matter or energy between the system and its surroundings.
A closed system allows for the exchange of energy between the system and its surroundings, but does not allow the exchange of matter. This is the definition of a closed system. An open system allows for the exchange of both matter and energy between the system and its surroundings. An isolated system on the other hand does not allow the exchange of either matter or energy between the system and its surroundings.
Compare your answer with the correct one above
When 
of liquid octane 
undergoes combustion in a bomb calorimeter, the temperature increases from 
degrees Celsius to 
degrees Celsius. The heat capacity for the bomb calorimeter is 
. Find the 
for the combustion of octane in 
.
When
Recall the following equation:
Now, since the bomb calorimeter keeps the volume constant, we know the following relationship:
Thus, we can then write the following equation for 
:
Start by finding 
:
From this, we know that 
Now, find 
.
Your answer must have 
significant figures.
Recall the following equation:
Now, since the bomb calorimeter keeps the volume constant, we know the following relationship:
Thus, we can then write the following equation for
Start by finding
From this, we know that
Now, find
Your answer must have
Compare your answer with the correct one above
How much heat energy is needed to raise the temperature of 
of copper from 
to 
? The specific heat capacity of copper is 
.
How much heat energy is needed to raise the temperature of
In this question, we're given the mass of copper, along with its specific heat capacity, and we're asked to determine the amount of heat energy necessary to increase its temperature by a given amount.
To solve this problem, we'll need to make use of the following equation.
Since we know what the values are for the mass and specific heat, we'll need to figure out what the temperature will be. Since the Kelvin and Celsius temperature scales both change by the same amount and only differ at their zero point, we can take the difference of the temperatures in degrees Celsius and use that value (since it will be equivalent to the change in the Kelvin temperature as well).
Plugging this information into the first expression, we can solve for the amount of heat energy that will bring this mass of copper to the desired temperature.
In this question, we're given the mass of copper, along with its specific heat capacity, and we're asked to determine the amount of heat energy necessary to increase its temperature by a given amount.
To solve this problem, we'll need to make use of the following equation.
Since we know what the values are for the mass and specific heat, we'll need to figure out what the temperature will be. Since the Kelvin and Celsius temperature scales both change by the same amount and only differ at their zero point, we can take the difference of the temperatures in degrees Celsius and use that value (since it will be equivalent to the change in the Kelvin temperature as well).
Plugging this information into the first expression, we can solve for the amount of heat energy that will bring this mass of copper to the desired temperature.
Compare your answer with the correct one above
Ice cubes are dropped into a glass of water. You notice that the glass of water becomes colder and condensation appears. Later in the day, you notice the glass of water is now room temperature and there is no more condensation. Which of the following concepts describes this process?
Ice cubes are dropped into a glass of water. You notice that the glass of water becomes colder and condensation appears. Later in the day, you notice the glass of water is now room temperature and there is no more condensation. Which of the following concepts describes this process?
Thermal equilibrium: Thermal energy of the system is equal to thermal energy of the surroundings. Heat is defined as the energy transfer resulting from differences in thermal energy. Heat always flows from higher temperature to lower temperature. Heat transfer between a system and its surroundings stop when they reach thermal equilibrium, or when there is no difference in thermal energy. In this case, ice was dropped into the cup. Initially, the ice increases the temperature of the water, creating a cold glass with condensation. However, energy from the surroundings flow into the system (the glass of water) due to thermal difference and warm the glass of water until the two reach thermal equilibrium. At thermal equilibrium, there is no ice, no condensation, and the water temperature is room temperature.
Thermal equilibrium: Thermal energy of the system is equal to thermal energy of the surroundings. Heat is defined as the energy transfer resulting from differences in thermal energy. Heat always flows from higher temperature to lower temperature. Heat transfer between a system and its surroundings stop when they reach thermal equilibrium, or when there is no difference in thermal energy. In this case, ice was dropped into the cup. Initially, the ice increases the temperature of the water, creating a cold glass with condensation. However, energy from the surroundings flow into the system (the glass of water) due to thermal difference and warm the glass of water until the two reach thermal equilibrium. At thermal equilibrium, there is no ice, no condensation, and the water temperature is room temperature.
Compare your answer with the correct one above