Thermodynamics MCQs

A large iceberg melts at the base, but not at the top, because of the reason that

by
A. Ice at the base contains impurities which lowers its melting point
B. Due to the high pressure at the base, its melting point reduces
C. The iceberg remains in a warmer condition at the base
D. All of the above
✅ The correct answer is option B.

High pressure steam is expanded adiabati-cally and reversibly through a well insulated turbine, which produces some shaft work. If the enthalpy change and entropy change across the turbine are represented by ΔH and ΔS respectively for this process:

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A. Δ H = 0 and ΔS = 0
B. Δ H ≠ 0 and ΔS = 0
C. Δ H ≠ 0 and ΔS ≠ 0
D. Δ H = 0 and ΔS ≠ 0
✅ The correct answer is option B.

For water at 300°C, it has a vapour pressure 8592.7 kPa and fugacity 6738.9 kPa Under these conditions, one mole of water in liquid phase has a volume of 25.28 cm³ and that in vapour phase in 391.1 cm³.Fugacity of water (in kPa) at 9000 kPa will be

by
A. 6738.9
B. 6753.5
C. 7058.3
D. 9000
✅ The correct answer is option B.