HEAT
1. Which of the following is a form of energy in transit?
a) Heat
b) Temperature
c) Thermal expansion
d) Specific heat capacity
2. Which theory describes heat as the motion of tiny particles?
a) Kinetic theory of heat
b) Laws of thermodynamics
c) Boyle's law
d) Charles's law
3. The Kelvin temperature scale is based on:
a) The freezing point of water
b) The boiling point of water
c) Absolute zero
d) The triple point of water
4. If the temperature of an object is increased, what happens to its molecules?
a) They move slower
b) They move faster
c) They remain stationary
d) They disappear
5. Which property of a material determines its ability to conduct heat?
a) Thermal expansion
b) Thermal conductivity
c) Specific heat capacity
d) Thermal equilibrium
6. A bimetallic thermostat works based on the principle of:
a) Thermal expansion
b) Specific heat capacity
c) Boyle's law
d) Charles's law
7. A bimetallic thermometer uses two metals with different:
a) Thermal conductivities
b) Melting points
c) Thermal expansions
d) Specific heat capacities
8. Boyle's law relates the pressure and volume of a gas at constant:
a) Temperature
b) Mass
c) Density
d) Velocity
9. Charles's law states that the volume of a gas is directly proportional to its:
a) Pressure
b) Temperature
c) Density
d) Velocity
10. The general gas law combines which three gas laws?
a) Boyle's, Charles's, and Gay-Lussac's laws
b) Dalton's, Henry's, and Graham's laws
c) Avogadro's, Faraday's, and Clausius's laws
d) Archimedes's, Pascal's, and Bernoulli's laws
11. According to the kinetic interpretation of gases, pressure is caused by:
a) The motion of gas molecules
b) The temperature of the gas
c) The volume of the container
d) The density of the gas
12. Heat capacity is defined as the amount of heat required to:
a) Raise the temperature of an object by 1 degree Celsius
b) Raise the temperature of an object by 1 degree Fahrenheit
c) Melt a substance completely
d) Vaporize a substance completely
13. Specific heat capacity is the amount of heat required to raise the temperature of:
a) One gram of a substance by 1 degree Celsius
b) One kilogram of a substance by 1 degree Celsius
c) One mole of a substance by 1 degree Celsius
d) One liter of a substance by 1 degree Celsius
14. The determination of specific heat capacity involves measuring the:
a) Temperature change and the mass of the substance
b) Pressure and volume of the gas
c) Length and diameter of a solid
d) Velocity and density of a fluid
15. Molar specific heat refers to the heat capacity of:
a) One gram of a substance
b) One kilogram of a substance
c) One mole of a substance
d) One liter of a substance
16. In thermodynamics, work is defined as the:
a) Transfer of energy by temperature difference
b) Transfer of energy by heat
c) Transfer of energy by radiation
d) Transfer of energy by mechanical means
17. The first law of thermodynamics is a statement of:
a) Conservation of energy
b) Conservation of mass
c) Conservation of momentum
d) Conservation of temperature
18. Special gases refer to those that:
a) Deviate from ideal gas behavior
b) Have high molar masses
c) Are found only in specific industries
d) Are used for medical purposes
19. The application of the first law of thermodynamics includes:
a) Heat engines
b) Electric circuits
c) Chemical reactions
d) Fluid dynamics
20. Cp - Cv = R represents the relationship between:
a) Heat capacity and specific heat capacity
b) Thermal expansion and temperature change
c) Pressure and volume of a gas
d) Specific heat capacities at constant pressure and volume
21. The value of the gas constant R in the ideal gas law is approximately:
a) 8.314 J/(mol·K)
b) 1.987 cal/(mol·K)
c) 0.0821 L·atm/(mol·K)
d) All of the above
22. The second law of thermodynamics states that:
a) Heat cannot flow from a colder object to a hotter object without external work
b) The total entropy of an isolated system always increases
c) The efficiency of a heat engine is always less than 100%
d) All of the above
23. The Carnot engine is a theoretical engine that operates:
a) Between two fixed temperatures and is reversible
b) By burning fossil fuels to generate power
c) By converting heat directly into electricity
d) By using solar energy to produce work
24. Entropy is a measure of:
a) Disorder or randomness in a system
b) The temperature of a system
c) The energy content of a system
d) The pressure exerted by a system
25. Which of the following is NOT a property of gases according to the kinetic molecular theory?
a) Gases consist of small particles in constant motion
b) Gas particles exert attractive forces on each other
c) Gas particles occupy a large volume compared to the container
d) The pressure of a gas is proportional to the average kinetic energy of its particles
26. Which law describes the relationship between the pressure and volume of a gas at constant temperature?
a) Boyle's law
b) Charles's law
c) Gay-Lussac's law
d) Dalton's law
27. The relationship between pressure and volume in Boyle's law is:
a) Inversely proportional
b) Directly proportional
c) Not related
d) Quadratically related
28. Charles's law states that, at constant pressure, the volume of a gas is directly proportional to its:
a) Temperature
b) Pressure
c) Mass
d) Density
29. According to the ideal gas law, PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the gas constant, and T is temperature. This equation combines which gas laws?
a) Boyle's law and Charles's law
b) Boyle's law and Gay-Lussac's law
c) Charles's law and Avogadro's law
d) Gay-Lussac's law and Avogadro's law
30. Which gas law relates the pressure and temperature of a gas at constant volume?
a) Gay-Lussac's law
b) Boyle's law
c) Dalton's law
d) Graham's law
31. The ratio of the specific heat capacities at constant pressure (Cp) and constant volume (Cv) for an ideal gas is equal to:
a) R, the gas constant
b) The molar mass of the gas
c) The temperature of the gas
d) The number of moles of the gas
32. The value of the gas constant R is different for different gases.
a) True
b) False
33. The change in internal energy of a system is given by the equation:
a) ΔU = Q + W
b) ΔU = Q - W
c) ΔU = Q × W
d) ΔU = Q / W
34. The efficiency of a heat engine is defined as:
a) The ratio of work output to heat input
b) The ratio of heat output to work input
c) The ratio of temperature increase to heat input
d) The ratio of pressure increase to work input
35. The efficiency of a Carnot engine operating between two temperatures T1 and T2 is given by:
a) 1 - T2/T1
b) 1 - T1/T2
c) T1 - T2
d) T2 - T1
36. The process in which a substance changes directly from a solid to a gas is called:
a) Sublimation
b) Condensation
c) Evaporation
d) Fusion
37. The Clausius-Clapeyron equation relates the:
a) Rate of reaction to the temperature
b) Rate of evaporation to the pressure
c) Rate of condensation to the volume
d) Rate of sublimation to the molar mass
38. The entropy of a system increases when:
a) Heat is transferred out of the system
b) Work is done on the system
c) The system reaches absolute zero temperature
d) The system moves from a state of higher probability to a state of lower probability
39. An isothermal process is a process in which:
a) The temperature remains constant
b) The pressure remains constant
c) The volume remains constant
d) The entropy remains constant
40. Which of the following is NOT an application of the first law of thermodynamics?
a) Refrigerators
b) Steam turbines
c) Nuclear power plants
d) Solar panels
41. The unit of entropy is:
a) Joule (J)
b) Kelvin (K)
c) Pascal (Pa)
d) Joule per Kelvin (J/K)
42. Which of the following is an example of an irreversible process?
a) Melting of ice
b) Boiling of water
c) Compressing a gas slowly
d) Mixing two gases together
43. The specific heat capacity of water is higher than that of most substances. This property is important for:
a) Maintaining a stable climate
b) Cooking food evenly
c) Generating electricity
d) Controlling industrial processes
44. The temperature at which the volume of an ideal gas becomes zero is called:
a) Absolute zero
b) Absolute pressure
c) Absolute temperature
d) Absolute entropy
45. The triple point of water occurs at a temperature and pressure where:
a) All three phases of water coexist in equilibrium
b) Water exists only as a gas
c) Water freezes at atmospheric pressure
d) Water boils at 100 degrees Celsius
46. Which of the following is a characteristic of an adiabatic process?
a) No heat transfer
b) Constant volume
c) Constant pressure
d) Reversible expansion
47. The kinetic theory of gases explains the behavior of gases based on:
a) The motion and collisions of gas particles
b) The forces between gas particles
c) The arrangement of gas particles in a lattice structure
d) The chemical properties of gas particles
48. The value of the gas constant R in the ideal gas law depends on:
a) The pressure of the gas
b) The volume of the gas
c) The temperature of the gas
d) The molar mass of the gas
49. The efficiency of a heat engine can be increased by:
a) Decreasing the temperature of the heat source
b) Increasing the temperature of the heat sink
c) Reducing friction in the engine
d) Increasing the amount of heat input
50. The concept of entropy is closely related to:
a) Disorder and randomness in a system
b) Energy conservation in a system
c) The pressure exerted by a system
d) The temperature of a system
ANSWER KEY:
- a) Heat
- a) Kinetic theory of heat
- c) Absolute zero
- b) They move faster
- b) Thermal conductivity
- a) Thermal expansion
- c) Thermal expansions
- a) Temperature
- b) Temperature
- a) Boyle's, Charles's, and Gay-Lussac's laws
- a) The motion of gas molecules
- a) Raise the temperature of an object by 1 degree Celsius
- a) One gram of a substance by 1 degree Celsius
- a) Temperature change and the mass of the substance
- c) One mole of a substance by 1 degree Celsius
- d) Transfer of energy by mechanical means
- a) Conservation of energy
- a) Deviate from ideal gas behavior
- a) Heat engines
- d) Specific heat capacities at constant pressure and volume
- a) 8.314 J/(mol·K)
- d) All of the above
- a) Between two fixed temperatures and is reversible
- a) Disorder or randomness in a system
- b) Gas particles exert attractive forces on each other
- a) Boyle's law
- a) Inversely proportional
- a) Temperature
- a) Boyle's law and Charles's law
- a) Gay-Lussac's law
- a) R, the gas constant
- a) True
- b) ΔU = Q - W
- a) The ratio of work output to heat input
- b) 1 - T1/T2
- a) Sublimation
- b) Rate of evaporation to the pressure
- d) The system moves from a state of higher probability to a state of lower probability
- a) The temperature remains constant
- a) Refrigerators
- d) Joule per Kelvin (J/K)
- d) Mixing two gases together
- a) Maintaining a stable climate
- a) Absolute zero
- a) All three phases of water coexist in equilibrium
- a) No heat transfer
- a) The motion and collisions of gas particles
- c) The temperature of the gas
- c) Reducing friction in the engine
- a) Disorder and randomness in a system
