A. Decreases in all spontaneous (or irreversible) processes
B. Change during a spontaneous process has a negative value
C. Remains unchanged in reversible processes carried at constant temperature and pressure
D. All A, B. and C
Related Mcqs:
- Gibbs free energy (G) is represented by, G = H – TS, whereas Helmholtz free energy, A. is given by, A = E – TS. Which of the following is the Gibbs-Helmholtz equation ?
A. [∂(G/T)/∂T] = – (H/T2)
B. [∂(A/T)/∂T]V = – E/T2
C. Both A. and B.
D. Neither A. nor B. - The main pollutant in waste water discharged from a petroleum refinery is oil (both in free and emulsified form). Free oil is removed by_________________?
A. Biological oxygen pond
B. Aerated lagoons
C. Trickling filters
D. Gravity separator having oil skimming devices - The ratio of existing moles of vapor per mole of vapor free gas to the moles of vapor that would be present per mole of vapor free gas, if the mixture were saturated at the existing temperature & pressure, is termed as the_____________________?
A. Relative humidity
B. Relative saturation
C. Percentage saturation
D. None of these - Gibbs free energy (F) is defined as__________________?
A. F = E – TS
B. F = H – TS
C. F = H + TS
D. F = E + TS - A chemical reaction will occur spontaneously at constant pressure and temperature, if the free energy is________________?
A. Zero
B. Positive
C. Negative
D. None of these - Gibbs free energy per mole for a pure substance is equal to the__________________?
A. Latent heat of vaporisation
B. Chemical potential
C. Molal boiling point
D. Heat capacity - Helmholtz free energy A. is defined as____________________?
A. A = H – TS
B. A = E – TS
C. A = H + TS
D. None of these - Free energy change of mixing two liquid substances is a function of the__________________?
A. Concentration of the constituents only
B. Quantities of the constituents only
C. Temperature only
D. All A, B. and C - Gibbs free energy at constant pressure and temperature under equilibrium conditions is___________________?
A. ∞
B. 0
C. Maximum
D. Minimum - The expression, ΔG = 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
