Chpt 6 First Law Of Thermodynamics Flashcards
1
Q
QUESTION
A
OPTION 1
2
Q
- What does the First Law of Thermodynamics state? (A) Energy is conserved in a closed system. (B) Energy can neither be created nor destroyed, only transformed. (C) Work and heat are interchangeable in all processes. (D) The internal energy of a system is constant.
A
Answer: B) Energy can neither be created nor destroyed, only transformed.
3
Q
- What is a thermodynamic system? (A) The part of the universe under investigation. (B) A system in equilibrium with its surroundings. (C) The surrounding environment. (D) The boundary that separates different phases of matter.
A
Answer: A) The part of the universe under investigation.
4
Q
- Which type of wall prevents both matter and energy from passing? (A) Adiabatic wall. (B) Impermeable wall. (C) Permeable wall. (D) Insulated wall.
A
Answer: A) Adiabatic wall.
5
Q
- Which type of system is described by a closed container with a volatile liquid? (A) Closed system. (B) Open system. (C) Isolated system. (D) Non-isolated system.
A
Answer: A) Closed system.
6
Q
- What defines the state of a system? (A) The values of measurable properties like temperature and pressure. (B) The history of the system’s energy changes. (C) The equilibrium condition of the system. (D) The path taken from one state to another.
A
Answer: A) The values of measurable properties like temperature and pressure.
7
Q
- Which of the following is an extensive property? (A) Mass. (B) Temperature. (C) Density. (D) Pressure.
A
Answer: A) Mass.
8
Q
- What is the nature of a reversible thermodynamic process? (A) The system proceeds through a series of equilibrium states. (B) The system changes quickly without equilibrium. (C) Energy is lost during the process. (D) Heat is absorbed by the system at a constant rate.
A
Answer: A) The system proceeds through a series of equilibrium states.
9
Q
- What is the characteristic of an adiabatic process? (A) No exchange of heat between the system and its surroundings. (B) The pressure remains constant. (C) The volume remains constant. (D) Work is done on the system.
A
Answer: A) No exchange of heat between the system and its surroundings.
10
Q
- Which of the following is a path function? (A) Heat. (B) Temperature. (C) Entropy. (D) Internal energy.
A
Answer: A) Heat.
11
Q
- Which system allows both energy and matter to exchange? (A) Open system. (B) Isolated system. (C) Closed system. (D) Adiabatic system.
A
Answer: A) Open system.
12
Q
- What is an example of an irreversible thermodynamic process? (A) Rapid compression of a gas. (B) Slow expansion of a gas at constant pressure. (C) Isothermal expansion of an ideal gas. (D) Constant heat absorption during a phase change.
A
Answer: A) Rapid compression of a gas.
13
Q
- In an isobaric process, what remains constant? (A) Pressure. (B) Volume. (C) Temperature. (D) Entropy.
A
Answer: A) Pressure.
14
Q
- What is the main difference between intensive and extensive properties? (A) Intensive properties are independent of the system’s mass. (B) Extensive properties do not depend on temperature. (C) Intensive properties depend on the amount of substance. (D) Extensive properties are always measurable directly.
A
Answer: A) Intensive properties are independent of the system’s mass.
15
Q
- Which of the following describes the concept of entropy? (A) The measure of disorder in a system. (B) The total energy available in a system. (C) The work done by the system. (D) The temperature of a system at equilibrium.
A
Answer: A) The measure of disorder in a system.
16
Q
- In which type of system can neither energy nor mass be exchanged? (A) Isolated system. (B) Open system. (C) Closed system. (D) Adiabatic system.
A
Answer: A) Isolated system.
17
Q
- What is the definition of internal energy (E)? (A) Energy associated with the kinetic and potential energy of molecules. (B) Energy due to external forces acting on a system. (C) The energy transferred by work or heat. (D) The energy lost to the surroundings during a process.
A
Answer: A) Energy associated with the kinetic and potential energy of molecules.
18
Q
- What does the second law of thermodynamics address? (A) The direction of energy transformations and equilibrium. (B) The amount of work that can be done by the system. (C) The conservation of total energy in a system. (D) The increase in internal energy during a reversible process.
A
Answer: A) The direction of energy transformations and equilibrium.
19
Q
- What is an example of a thermodynamic process that is cyclic? (A) A refrigerator cooling a room. (B) A gas expanding and then contracting in a piston. (C) Heat being transferred to a system at constant pressure. (D) Water boiling at a constant temperature.
A
Answer: B) A gas expanding and then contracting in a piston.
20
Q
- Which of the following properties is independent of the mass of the substance? (A) Specific heat. (B) Volume. (C) Pressure. (D) Mass.
A
Answer: A) Specific heat.
21
Q
- What is the purpose of the third law of thermodynamics? (A) To evaluate the behavior of entropy as temperature approaches absolute zero. (B) To describe the relationship between heat and temperature. (C) To measure the total work done by a system. (D) To predict the spontaneity of chemical reactions.
A
Answer: A) To evaluate the behavior of entropy as temperature approaches absolute zero.
22
Q
QUESTION
A
OPTION 1
23
Q
- What is work defined as in thermodynamics? (a) The result of action against an opposing force (b) The flow of heat in a system (c) The change in internal energy (d) The pressure exerted by a gas
A
Answer: (a) The result of action against an opposing force
24
Q
- Which of the following is a path-dependent function? (a) Work (b) Temperature (c) Enthalpy (d) Internal energy
A
Answer: (a) Work
25
Q
- What happens when work is done under constant pressure? (a) It is equal to the change in internal energy (b) It is equal to the change in enthalpy (c) It does not depend on the path of the process (d) It cannot be calculated
A
Answer: (b) It is equal to the change in enthalpy
26
Q
- What is the heat absorbed at constant volume equal to? (a) The change in internal energy (b) The work done by the system (c) The pressure-volume work (d) The change in enthalpy
A
Answer: (a) The change in internal energy
27
Q
- In a process with only PV work, what is the heat absorbed at constant pressure equal to? (a) The change in internal energy (b) The change in enthalpy (c) The work done (d) The volume change
A
Answer: (b) The change in enthalpy
28
Q
- What is enthalpy defined as? (a) H = E + PV (b) H = E - PV (c) H = P + V (d) H = E + T
A
Answer: (a) H = E + PV
29
Q
- Which of the following is true about the first law of thermodynamics? (a) Energy is conserved (b) Heat and work are the same (c) Only internal energy can be measured (d) Work done is always positive
A
Answer: (a) Energy is conserved
30
Q
- The heat absorbed during a constant volume process is a function of which variable? (a) Internal energy (b) Enthalpy (c) Pressure (d) Work
A
Answer: (a) Internal energy
31
Q
- What does the symbol “Cp” represent? (a) Heat capacity at constant pressure (b) Heat capacity at constant volume (c) Specific heat at constant pressure (d) Molar heat capacity at constant volume
A
Answer: (a) Heat capacity at constant pressure
32
Q
- For a monoatomic ideal gas, the heat capacity at constant volume (Cv) is equal to? (a) (3/2)R (b) (5/2)R (c) (7/2)R (d) (2/2)R
A
Answer: (a) (3/2)R
33
Q
- What is the heat capacity at constant pressure (Cp) for a diatomic gas (ignoring vibrational energy)? (a) (5/2)R (b) (3/2)R (c) (7/2)R (d) R
A
Answer: (a) (5/2)R
34
Q
- What is the change in internal energy during an isothermal process? (a) Zero (b) Positive (c) Negative (d) Depends on volume
A
Answer: (a) Zero
35
Q
- The heat absorbed in a process at constant pressure exceeds the heat absorbed at constant volume by? (a) PΔV (b) ΔE (c) ΔH (d) TΔS
A
Answer: (a) PΔV
36
Q
- What is the general equation for calculating work done during expansion? (a) W = PΔV (b) W = E + PV (c) W = ΔE + PΔV (d) W = ΔH + PΔV
A
Answer: (a) W = PΔV
37
Q
- How is heat capacity defined? (a) The rate of change of heat with temperature (b) The energy needed to increase the temperature by one degree (c) The energy needed to change pressure by one unit (d) The amount of heat required to maintain constant volume
A
Answer: (b) The energy needed to increase the temperature by one degree
38
Q
- What is the relationship between Cp and Cv for an ideal gas? (a) Cp > Cv (b) Cp = Cv (c) Cp < Cv (d) Cp = 0
A
Answer: (a) Cp > Cv
39
Q
- How is the specific heat capacity at constant volume (Cv) for a monoatomic gas calculated? (a) (3/2)R (b) (5/2)R (c) R (d) 2R
A
Answer: (a) (3/2)R
40
Q
- What does the term “molar heat capacity” refer to? (a) Heat capacity of one mole of substance (b) Heat capacity of one gram of substance (c) Heat capacity of a solid element (d) Heat capacity of a diatomic molecule
A
Answer: (a) Heat capacity of one mole of substance
41
Q
- What is the heat capacity at constant pressure (Cp) for a gas? (a) The energy required to increase the temperature at constant pressure (b) The energy required to increase the temperature at constant volume (c) The heat absorbed during expansion (d) The work done by the system
A
Answer: (a) The energy required to increase the temperature at constant pressure
42
Q
- Which of the following is a key feature of the Duong and Petit Law? (a) It relates heat capacity to temperature (b) It calculates work done in a reversible process (c) It measures the change in enthalpy during expansion (d) It defines the ideal gas law
A
Answer: (a) It relates heat capacity to temperature
