Description : In a totally irreversible isothermal expansion process for an ideal gas, ΔE = 0, ΔH = 0. Then ΔQ and ΔS will be (A) ΔQ = 0, ΔS=0 (B) ΔQ = 0, ΔS = +ve (C) ΔQ = 0, ΔS = -ve (D) ΔQ = +ve, ΔS= +ve
Last Answer : (B) ΔQ = 0, ΔS = +ve
Description : For an exothermic reaction (A) Only enthalpy change (ΔH) is negative (B) Only internal energy change (ΔE) is negative (C) Both ΔH and ΔE are negative (D) Enthalpy change is zero
Last Answer : (C) Both ΔH and ΔE are negative
Description : . The entropy change in a reversible isothermal process, when an ideal gas expands to four times its initial volume is (A) R loge 4 (B) R log10 4 (C) Cv log10 4 (D) Cv loge 4
Last Answer : (A) R loge 4
Description : The expression for entropy change given by, ΔS = - nR ln (P2/P1), holds good for (A) Expansion of a real gas (B) Reversible isothermal volume change (C) Heating of an ideal gas (D) Cooling of a real gas
Last Answer : (B) Reversible isothermal volume change
Description : The expression, ∆G = nRT. ln(P2/P1), gives the free energy change (A) With pressure changes at constant temperature (B) Under reversible isothermal volume change (C) During heating of an ideal gas (D) During cooling of an ideal gas
Last Answer : (A) With pressure changes at constant temperature
Description : On a P-V diagram of an ideal gas, suppose a reversible adiabatic line intersects a reversible isothermal line at point A. Then at a point A, the slope of the reversible adiabatic line (∂P/∂V)s and the slope of the reversible isothermal line ... Y (C) (∂P/∂V)S = y(∂P/∂V)T (D) (∂P/∂V)S = 1/y(∂P/∂V)T
Last Answer : (C) (∂P/∂V)S = y(∂P/∂V)T
Description : The expression for entropy change given by, ΔS = nR ln (V2/V1) + nCvln (T2/T1) is valid for (A) Reversible isothermal volume change (B) Heating of a substance (C) Cooling of a substance (D) Simultaneous heating and expansion of an ideal gas
Last Answer : (D) Simultaneous heating and expansion of an ideal gas
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 : For the reversible isothermal expansion of one mole of an ideal gas at 300 K, from a volume of `10 dm^(3)` to `20 dm^(3), Delta H` is -
Last Answer : For the reversible isothermal expansion of one mole of an ideal gas at 300 K, from a volume of `10 dm^(3)` to ` ... . `-1.73 KJ` C. `3.46 KJ` D. Zero
Description : Pick out the correct statement. (A) The available energy in an isolated system for all irreversible (real) processes decreases (B) The efficiency of a Carnot engine increases, if the sink temperature is decreased ... condition is the change in Helmholtz free energy (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Which of the following non-flow reversible compression processes require maximum work? (A) Adiabatic process (B) Isothermal process (C) Isobaric process (D) All require same work
Last Answer : (A) Adiabatic process
Description : The change in __________ is equal to the reversible work for compression in steady state flow process under isothermal condition. (A) Internal energy (B) Enthalpy (C) Gibbs free energy (D) Helmholtz free energy
Last Answer : (C) Gibbs free energy
Description : The ammonia synthesis reaction represented by N2 + 3H2 ⇌ 2NH3; ΔH = - 22.4 kcal, is (A) Endothermic (B) Exothermic (C) Isothermal (D) Adiabatic
Last Answer : (B) Exothermic
Description : Which of the following processes cannot be made reversible even under ideal condition of operation? (A) Free expansion of a gas (B) Compression of air in a compressor (C) Expansion of steam in a turbine (D) All (A), (B) & (C)
Last Answer : (A) Free expansion of a gas
Description : Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = Cp/Cv = 7/5) and the process to be reversible, is (A) 300 × (32/7) (B) 300 × (33/5) (C) 300 × (333/7) (D) 300 × (35/7)
Last Answer : A) 300 × (32/7)
Description : For a constant pressure reversible process, the enthalpy change (ΔH) of the system is (A) Cv.dT (B) Cp.dT (C) ∫ Cp.dT (D) ∫ Cv.dT
Last Answer : (C) ∫ Cp.dT
Description : Ideal process are ________ process a. Irreversible b. Reversible c. Isothermal d. Isometric
Last Answer : Reversible
Description : Which of the following equations is obtained on combining 1st and 2nd law of thermodynamics, for a system of constant mass? (A) dE = Tds - PdV (B) dQ = CvdT + PdV (C) dQ = CpdT + Vdp (D) Tds = dE - PdV
Last Answer : (A) dE = Tds - PdV
Description : First law of thermodynamics is mathematically stated as (A) dQ = dE + dW (B) dQ = dE - dW (C) dE = dQ + dW (D) dW = dQ + dE
Last Answer : First law of thermodynamics is mathematically stated as (A) dQ = dE + dW (B) dQ = dE - dW (C) dE = dQ + dW (D) dW = dQ + dE
Description : For a constant volume process (A) dE = CpdT (B) dE = CvdT (C) dQ = dE + pdV (D) dW = pdV
Last Answer : (B) dE = CvdT
Description : An isothermal aqueous phase reversible reaction, P ⇌ R, is to be carried out in a mixed flow reactor. The reaction rate in k.mole/m3 .h is given by, r = 0.5CP - 0.125CR. A stream containing only P enters the reactor. The ... (in hours) for 40% conversion of P is (A) 0.80 (B) 1.33 (C) 1.60 (D) 2.67
Last Answer : (C) 1.60
Description : When a gas in a vessel expands, its internal energy decreases. The process involved is (A) Reversible (B) Irreversible (C) Isothermal (D) Adiabatic
Last Answer : (A) Reversible
Description : In the equation, PVn = Constant, if the value of n = 0, then it represents a reversible __________ process. (A) Isobaric (B) Isothermal (C) Isentropic (D) Isometric
Last Answer : (A) Isobaric
Description : In an isothermal process on an ideal gas, the pressure increases by 0.5 percent. The volume decreases by about __________ percent. (A) 0.25 (B) 0.5 (C) 0.75 (D) 1
Last Answer : (B) 0.5
Description : The difference between isothermal compressibility and adiabatic compressibility for an ideal gas is (A) 0 (B) +ve (C) -ve (D) ∞
Last Answer : (B) +ve
Description : Pick out the correct statement. (A) Like internal energy and enthalpy, the absolute value of standard entropy for elementary substances is zero (B) Melting of ice involves increase in enthalpy and ... of an ideal gas depends only on its pressure (D) Maximum work is done under reversible conditions
Last Answer : (D) Maximum work is done under reversible conditions
Description : An autothermal reactor is (A) Most suitable for a second order reaction (B) Most suitable for a reversible reaction (C) Completely self-supporting in its thermal energy requirements (D) Isothermal in nature
Last Answer : (C) Completely self-supporting in its thermal energy requirements
Description : In polytropic process (PV n = constant), if n = 1; it means a/an __________ process. (A) Adiabatic (B) Reversible (C) Isothermal (D) None of these
Last Answer : (C) Isothermal
Description : PVy = constant, holds good for an isentropic process, which is (A) Reversible and isothermal (B) Isothermal and irreversible (C) Reversible and adiabatic (D) Adiabatic and irreversible
Last Answer : C) Reversible and adiabatic
Description : In the equation, PVn = constant, if the value of n = ± ∞, then it represents a reversible __________ process. (A) Adiabatic (B) Isometric (C) Isentropic (D) Isothermal
Last Answer : (B) Isometric
Description : Pick out the correct statement: (A) In an isothermal system, irreversible work is more than reversible work (B) Under reversible conditions, the adiabatic work is less than isothermal work (C) ... state functions' (D) Matter and energy cannot be exchanged with the surroundings in a closed system
Last Answer : (B) Under reversible conditions, the adiabatic work is less than isothermal work
Description : Entropy of a substance remains constant during a/an __________ change. (A) Reversible isothermal (B) Irreversible isothermal (C) Reversible adiabatic (D) None of these
Last Answer : (C) Reversible adiabatic
Description : Throttling process is a/an __________ process. (A) Reversible and isothermal (B) Irreversible and constant enthalpy (C) Reversible and constant entropy (D) Reversible and constant enthalpy
Last Answer : (B) Irreversible and constant enthalpy
Description : The expression for the work done for a reversible polytropic process can be used to obtain the expression for work done for all processes, except reversible __________ process. (A) Isobaric (B) Isothermal (C) Adiabatic (D) None of these
Last Answer : (B) Isothermal
Description : In the equation PVn = constant, if the value of n = y = Cp/Cv, then it represents a reversible __________ process. (A) Isothermal (B) Adiabatic (C) Isentropic (D) Polytropic
Last Answer : (C) Isentropic
Description : In the equation, PVn = constant, if the value of n = 1, then it represents a reversible __________ process. (A) Isothermal (B) Isobaric (C) Polytropic (D) Adiabatic
Last Answer : (A) Isothermal
Description : In a P-V diagram (for an ideal gas), an isothermal curve will coincide within adiabatic curve (through a point), when (A) Cp < Cv (B) Cp = Cv (C) Cp > Cv (D) C ≥ Cv
Last Answer : (B) Cp = Cv
Description : The expression, nRT ln(P1/P2), is for the __________of an ideal gas. (A) Compressibility (B) Work done under adiabatic condition (C) Work done under isothermal condition (D) Co-efficient of thermal expansion
Last Answer : C) Work done under isothermal condition
Description : The propagation of sound waves in a gas involves – (1) Adiabatic compression and rarefaction (2) Isothermal compression and rarefaction (3) Isochoric compression and rarefaction (4) Isobaric compression and rarefaction
Last Answer : (1) Adiabatic compression and rarefaction Explanation: Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the ... . Through solids, however, it can be transmitted as both longitudinal waves and transverse waves.
Last Answer : (1) Adiabatic compression and rarefaction Explanation: Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within ... is transmitted through gases, plasma, and liquids as longitudinal waves, also called compression waves.
Description : When the expansion of compression of gas takes place without transfer of heat or from the gas the process is called; a. Isometric process b. Isothermal process c. Isobaric process d. Adiabatic process
Last Answer : Adiabatic process
Description : The propagation of sound waves in a gas involves (1) adiabatic compression and rarefaction (2) isothermal compression and rarefaction (3) isochoric compression and rarefaction (4) isobaric compression and rarefaction
Last Answer : adiabatic compression and rarefaction
Description : A piston filled with `0.04` mole of an ideal gas expands reversible from `50.0mL` at a constant temperature of `37.0^(@)C` . As it does so, it absorbs
Last Answer : A piston filled with `0.04` mole of an ideal gas expands reversible from `50.0mL` at a constant temperature of `37. ... J` D. `q= +208 J, w=+208 J`
Description : For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant (A) Is independent of pressure (B) Increases with pressure (C) Decreases with pressure (D) Increases /decreases with pressure depending on the stoichiometric coefficients of the reaction
Last Answer : (B) Increases with pressure
Description : Which of the following is not a reversible process? (A) Expansion of an ideal gas against constant pressure (B) Atmospheric pressure vaporisation of water at 100°C (C) Solution of NaCl in water at 50°C (D) None of these
Last Answer : C) Solution of NaCl in water at 50°C
Description : In a reversible process (A) Tds = dE + dW (B) dE - dW = Tds (C) dW - dE = Tds (D) Tds - dW + dE >0
Last Answer : (A) Tds = dE + dW
Description : Identify the correct statement. (A) Sphlerite is zinc oxide (B) The first law of the thermodynamics is stated as δE = δQ - δW (C) Lead can be produced in a blast furnace (D) T. ferrooxidans is a fungus that can be used for leaching chalcopyrite
Last Answer : Option A
Description : For a reversible process at T = 300K, the volume is increased from `V_(i)=1L` to `V_(f)=10L`. Calculate `Delta H` if the process is isothermal -
Last Answer : For a reversible process at T = 300K, the volume is increased from `V_(i)=1L` to `V_(f)=10L`. Calculate `Delta H ... kJ B. 4.98 kJ C. 0 D. `-11.47 kJ`
Description : What is polytropic process ? Under what conditions it approaches isobaric, isothermal, and isometric process ? In which reversible process no work is done ?
Last Answer : A polytropic process is one that follows the equation pun = constant (index n may have values from – oc to + oo. This process approaches isobaric when n = 0, isothermal when n = 1, and isometric when n = . No work is done in isometric process.