deck test Flashcards
What is the first law of thermodynamics?
Energy cannot be created or destroyed, only transformed.
True or False: The second law of thermodynamics states that entropy of an isolated system always increases.
True
Fill in the blank: The formula for work done by a gas is ___ = P × ΔV.
W
What does the symbol ‘Q’ represent in thermodynamics?
Heat transfer
What is the formula for calculating the change in internal energy (ΔU)?
ΔU = Q - W
Multiple choice: Which equation represents the ideal gas law? A) PV = nRT B) E = mc² C) F = ma
A) PV = nRT
What is enthalpy (H) defined as?
H = U + PV
True or False: The specific heat capacity is the amount of heat required to change the temperature of a unit mass by one degree.
True
What is the formula for calculating the efficiency (η) of a heat engine?
η = (W_out / Q_in) × 100%
Fill in the blank: The third law of thermodynamics states that as temperature approaches absolute zero, the entropy of a perfect crystal approaches ___.
zero
What does the term ‘adiabatic process’ mean?
A process in which no heat is exchanged with the surroundings.
Multiple choice: Which of the following is not a thermodynamic state function? A) Temperature B) Heat C) Pressure
B) Heat
What is the relationship between temperature and kinetic energy in thermodynamics?
Temperature is proportional to the average kinetic energy of particles.
True or False: In a closed system, mass can enter or leave the system.
False
What is the formula for calculating work done during an isothermal expansion of an ideal gas?
W = nRT ln(V_f / V_i)
Fill in the blank: The Carnot cycle is an idealized thermodynamic cycle that provides the maximum possible efficiency for a ___.
heat engine
What does the term ‘thermal equilibrium’ mean?
A state where two objects in contact do not exchange heat.
Multiple choice: Which of the following processes is exothermic? A) Melting ice B) Combustion of fuel C) Evaporation of water
B) Combustion of fuel
What is the formula for the Gibbs free energy (G)?
G = H - TS
True or False: The Clausius statement of the second law states that no process is possible whose sole result is the transfer of heat from a cooler to a hotter body.
True
What is the significance of absolute zero in thermodynamics?
It is the lowest possible temperature where molecular motion stops.
Fill in the blank: The heat capacity at constant volume is denoted as ___.
C_v
What is the formula for calculating the change in entropy (ΔS)?
ΔS = Q_rev / T
Multiple choice: Which law states that the total entropy of an isolated system can never decrease? A) Zeroth Law B) First Law C) Second Law
C) Second Law
What does the term ‘isothermal process’ refer to?
A process in which the temperature remains constant.
True or False: The heat engine converts thermal energy into mechanical work.
True
