(a)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(a)
Answer to Problem 18.21QP
The temperature of the given water sample will increase gradually, and water will evaporate in the room. This is a spontaneous process.
Explanation of Solution
To give: The change in the water sample
Given information,
The temperature of the given water sample will increase gradually, and then water sample will evaporate in the room. This is a spontaneous process.
(b)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(b)
Answer to Problem 18.21QP
The sign of enthalpy is positive, since heat is absorbed for evaporation process. The sign of entropy change is positive because water molecules changed their state from liquid to gas.
Explanation of Solution
To give: The enthalpy change of the water sample
Given information,
The sign of enthalpy is positive, since heat is absorbed by the water sample for evaporation process. The sign of entropy is positive because water molecules changed their state from liquid to gas (free movement of molecules).
(c)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(c)
Answer to Problem 18.21QP
The water molecules are easily moving and in higher temperature. Hence, the sign of entropy change is positive. The sign of enthalpy change is already positive, so the only way to have a spontaneous process is when the sign of entropy change is also positive.
Explanation of Solution
To give: The entropy change of the water sample
Given information,
The water molecules are in easily moving state and in higher temperature. Hence, the sign of entropy change is positive.
Given process is a spontaneous process, the sign of enthalpy change is already positive, so the sign of entropy change is should be positive.
(d)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(d)
Answer to Problem 18.21QP
Given process is a spontaneous process. Hence, the sign of free energy change is negative.
Explanation of Solution
To give: The free energy change of the water sample
Given information,
Given process is a spontaneous process, hence, the sign of free energy should be negative.
For a spontaneous process
(e)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(e)
Answer to Problem 18.21QP
The temperature of the given water sample will decrease gradually, and then water will evaporate in the room. This is spontaneous process.
Explanation of Solution
To give: The change in the water sample
Given information,
The temperature of the given water sample will decrease gradually, and then water will evaporate in the room. This is a spontaneous process.
(f)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(f)
Answer to Problem 18.21QP
The sign of enthalpy is negative because heat is released from water sample. The entropy change is positive because water molecules are escaping into the gaseous state.
Explanation of Solution
To give: The enthalpy change of the water sample
Given information,
The sign of enthalpy is negative
The entropy change is positive
(g)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(g)
Answer to Problem 18.21QP
The sign of entropy change is negative because water molecules are at a lower temperature and their movement is slow. But, some water molecules evaporates and becomes vapor state this process will increases the entropy.
Explanation of Solution
To give: The entropy change of the water sample
Given information,
The sign of entropy change is negative because water molecules are at a lower temperature and their movement is slow.
But, some water molecules evaporates and becomes vapor state this process will increases the entropy.
(h)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(h)
Answer to Problem 18.21QP
Given process is a spontaneous process. Hence, the sign of free energy change is negative.
Explanation of Solution
To give: The free energy change of the water sample
Given information,
Given process is a spontaneous process, hence, the sign of free energy should be negative.
For a spontaneous process
(i)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(i)
Answer to Problem 18.21QP
The temperature of the water will not change, and water molecules will evaporate, this is a spontaneous process.
Explanation of Solution
To give: The change in the water sample
Given information,
The temperature of the water will not change, and water molecules will evaporate, this is a spontaneous process.
(j)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(j)
Answer to Problem 18.21QP
The sign of enthalpy is positive because heat is absorbed by water molecules for their evaporation. The sign of entropy change is positive because the phase changes of water molecules from liquid to gas.
Explanation of Solution
To give: The enthalpy change of the water sample
Given information,
The sign of enthalpy change is positive, since heat is absorbed by the water sample for evaporation process.
The sign of entropy change is positive because water molecules changed their state from liquid to gas (free movement of molecules).
(k)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(k)
Answer to Problem 18.21QP
For a spontaneous process the sign of free energy change should be positive, here the sign of enthalpy change is already positive so the sign of entropy change should be positive.
Explanation of Solution
To give: The entropy change of the water sample
Given information,
For a spontaneous process
Given process is a spontaneous process, the sign of enthalpy change is already positive, so the sign of entropy change should be positive.
(l)
Interpretation:
For the given water sample various changes in enthalpy, entropy and free energy with temperature has to be explained.
Concept introduction:
Free energy:
Free energy is measured by subtracting the product of temperature and entropy from the enthalpy of a system.
Relationship between
(l)
Answer to Problem 18.21QP
Given process is a spontaneous process. Hence, the sign of free energy change is negative.
Explanation of Solution
To give: The free energy change of the water sample
Given information,
Given process is a spontaneous process, hence, the sign of free energy change should be negative.
For a spontaneous process
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Chapter 18 Solutions
General Chemistry - Standalone book (MindTap Course List)
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