Description : Change in enthalpy in a closed system is equal to heat transferred if the reversible process takes place at constant (a) pressure (b) temperature (c) volume (d) internal energy (e) entropy.
Last Answer : Answer : a
Description : According to first law of thermodynamics (a) work done by a system is equal to heat transferred by the system (b) total internal energy of a system during a process remains constant ( ... , enthalpy and entropy during a process remain constant (d) total energy of a system remains constant
Last Answer : Answer : d
Description : Which of the following occurs in a reversible polytrophic process? a. Enthalpy remains constant b. Internal energy does not change c. Some heat transfer occurs d. Entropy remains constant
Last Answer : Some heat transfer occurs
Description : If heat be exchanged in a reversible manner, which of the following property of the working substance will change accordingly (a) temperature (b) enthalpy (c) internal energy (d) entropy (e) all of the above.
Description : Change in enthalpy of a system is the heat supplied at (a) constant pressure (b) constant temperature (c) constant volume (d) constant entropy (e) N.T.P. condition.
Description : During throttling process (a) heat exchange does not take place (b) no work is done by expanding steam (c) there is no change of internal energy of steam (d) all of the above (e) entropy decreases.
Description : Which of the following is the property of a system (a) pressure and temperature (b) internal energy (c) volume and density (d) enthalpy and entropy (e) all of the above.
Last Answer : Answer : e
Description : In a Carnot cycle, heat is transferred at (a) constant pressure (b) constant volume (c) constant temperature (d) constant enthaply (e) any one of the above.
Last Answer : Answer : c
Description : If value of n is infinitely large in a polytropic process pV” = C, then the process is known as constant (a) volume (b) pressure (c) temperature (d) enthalpy (e) entropy
Description : If a system after undergoing a series of processes, returns to the initial state then (a) process is thermodynamically in equilibrium (b) process is executed in closed system cycle (c) its entropy will ... sum of heat and work transfer will be zero (e) no work will be done by the system.
Description : During adiabatic, internally reversible process, what is true about the change in entropy? A. It is temperature-dependent B. It is always greater than zero C. It is always zero D. It is always less than zero
Last Answer : It is always zero
Description : Entropy change depends on (a) heat transfer (b) mass transfer (c) change of temperature (d) thermodynamic state (e) change of pressure and volume.
Description : According to Avogadro's Hypothesis (a) the molecular weights of all the perfect gases occupy the same volume under same conditions of pressure and temperature (b) the sum of partial pressure of ... gases have two values of specific heat (e) all systems can be regarded as closed systems.
Description : For reversible adiabatic process, change in entropy is (a) maximum (b) minimum (c) zero (d) unpredictable (e) negative
Description : Which of the following parameters is constant for a mole for most of the gases at a given temperature and pressure (a) enthalpy (b) volume (c) mass (d) entropy (e) specific volume.
Last Answer : Answer : b
Description : First law of thermodynamics (a) enables to determine change in internal energy of the system (b) does not help to predict whether the system will or not undergo a change (c) does not enable ... entropy (d) provides relationship between heat, work and internal energy (e) all of the above.
Description : Entropy is transferred by ______. A. Work B. Heat C. Energy D. Work and heat
Last Answer : Heat
Description : What is referred to by control volume? a. An isolated system b. Closed system c. Fixed region in space d. Reversible process only
Last Answer : Fixed region in space
Description : The sum of internal energy (U) and the product of pressure and volume (p.v) is known as A. workdone B. entropy C. enthalpy D. none of these
Last Answer : Answer: C
Description : When the expansion of compression of gas takes place without transfer of heat to or from the gas the process is called a. reversible b. adiabatic c. polytropic d. isothermal
Last Answer : adiabatic
Description : Entropy is the measure of: a. The internal energy of a gas b. The heat capacity of a substance c. Randomness or disorder d. The change of enthalpy of a system
Last Answer : Randomness or disorder
Description : Which of the following processes are thermodynamically reversible (a) throttling (b) free expansion (c) constant volume and constant pressure (d) hyperbolic and pV = C (e) isothermal and adiabatic.
Description : Ten cu. ft of air at 300psia and 400°F is cooled to 140°F at constant volume. What is the transferred heat? a.-120Btu b. -220Btu c.-320Btu d. -420Btu formula: Q= mcv(T2-T1)
Last Answer : -420Btu
Description : Total heat of a substance is also known as (a) internal energy (b) entropy (c) thermal capacity (d) enthalpy (e) thermal conductance.
Description : An adiabatic process is one in which A.no heat enters or leaves the gas B.the temperature of the gas changes C.the change in internal energy is equal to the mechanical workdone D.all of the above
Last Answer : Answer: D
Description : What is the energy absorbed during chemical reaction under constant volume conditions? A. Entropy B. Ion exchange C. Enthalpy D. Enthalpy of reaction
Last Answer : Enthalpy
Description : What is the measure of the energy that is no longer available to perform useful work within the current environment? a. enthalpy b. entropy c. internal energy d. latent heat
Last Answer : entropy
Description : What is known as the total heat and heat content at various times in the history? a. enthalpy b. entropy c. internal energy d. latent heat
Last Answer : enthalpy
Description : What is the area under the curve on a temperature –entropy diagram? a. Heat b. work c. entropy d. volume
Description : When the gas is heated at constant volume, the heat supplied increases the internal energy of the gas. A.True B.False
Last Answer : Answer: A
Description : What is an energy that can be transferred from one object to another causing a change in temperature of each object? A. Power B. Heat transfer C. Heat D. Work
Description : What is considered as the heat content of a system? A. Enthalpy B. Entropy C. Internal heat D. Molar heat
Description : Universal gas constant is defined as equal to product of the molecular weight of the gas and (a) specific heat at constant pressure (b) specific heat at constant volume (c) ratio of two specific heats (d) gas constant (e) unity.
Description : Sum of the internal energy of a substance and the product of pressure and volume. a. Specific Heat b. Specific Gravity c. Isolated System d. Enthalpy
Description : In order that a cycle be reversible, following must be satisfied (a) free expansion or friction resisted expansion/compression process should not be encountered (b) when heat is being absorbed, temperature of hot ... sub-stance should be same (d) all of the above (e) none of the above.
Description : A gas is compressed in a cylinder by a movable piston to a volume onehalf its original volume. During the process 300 kJ heat left the gas and internal energy remained same. The work done on gas in Nm will be (a) 300 Nm (b) 300,000 Nm (c) 30 Nm (d) 3000 Nm (e) 30,000 Nm.
Description : How does an adiabatic process compare to an isentropic process? A. Adiabatic heat transfer is not equal to zero; isentropic heat transfer is zero B. Both heat transfer = 0; isentropic: reversible ... is not equal to zero D. Both heat transfer is not equal to zero; isentropic: irreversible
Last Answer : Both heat transfer = 0; isentropic: reversible
Description : Addition of heat at constant pressure to a gas results in (a) raising its temperature (b) raising its pressure (c) raising its volume (d) raising its temperature and doing external work (e) doing external work.
Description : Which of the following represents the perpetual motion of the first kind (a) engine with 100% thermal efficiency (b) a fully reversible engine (c) transfer of heat energy from low ... its own energy (e) production of energy by temperature differential in sea water at different levels.
Description : A heat exchange process in which the product of pressure and volume remains constant is known as (a) heat exchange process (b) throttling process (c) isentropic process (d) adiabatic process (e) hyperbolic process.
Description : The value of specific heat at constant pressure (cp) is __________ that of at constant volume (cv). A. less than B. equal to C. more than
Description : The ratio of specific heat at constant pressure (Cp) and specific heat at constant volume (cv) is A. equal to one B. less than one C. greater than one D. none of these
Description : According to Clausis statement of second law of thermodynamics (a) heat can't be transferred from low temperature source to high temperature source (b) heat can be transferred for low temperature to ... to high temperature source without the aid of external energy (e) all of the above.
Description : The entropy change of a system during a process is equal to the net entropy transfer through the system boundary and the entropy generated within the system . This statement is known as: A. Entropy ... B. Entropy change of a system C. Entropy balance relation D. Third law of thermodynamics
Last Answer : Entropy balance relation
Description : What refers to the heat needed to change the temperature of the substances without changing its phases? a. Latent heat b. Sensible heat c. Specific heat d. entropy
Last Answer : Sensible heat
Description : A series of operations, which takes place in a certain order and restore the initial conditions at the end, is known as A. reversible cycle B. irreversible cycle C. thermodynamic cycle D. none of these
Description : The volume of a confined gas is held constant, the pressure is directly proportional to the absolute temperature. a. Charle’s Law b. Boyle’s Law c. Joule’s Law d. Specific Heat
Last Answer : Boyle’s Law
Description : The heat supplied to the gaS at constant volume is (where m = Mass of gas, cv = Specific heat at constant volume, cp = Specific heat at constant pressure, T2 – T1 = Rise in temperature, and R = Gas constant) A. mR(T2 – T1) B. mcv(T2 – T1) C. mcp(T2 – T1) D. mcp(T2 + T1)
Last Answer : Answer: B
Description : The specific heat at constant volume is A. the amount of heat required to raise the temperature of unit mass of gas through one degree, at constant pressure B. the amount of heat required to raise ... to raise the temperature of 1 kg of water through one degree D. any one of the above
Description : The amount of heat required to raise the temperature of the unit mass of gas through one degree at constant volume, is called A.specific heat at constant volume B.specific heat at constant pressure C.kilo Joule D.none of these