Chemical Thermodynamics and Energetic
Which of the following pairs is an intensive property?
(A) Density, viscosity
(B) Surface tension, mass
(C) Viscosity, internal energy
(D) Heat capacity, volume
For a certain reaction, ∆H = − 50 kJ and ∆S = − 80 J K-1, at what temperature does the
reaction turn from spontaneous to non-spontaneous?
(A) 6.25 K
(B) 62.5 K
(C) 625 K
(D) 6250 K
One mole of a gas expands by 3L against a constant pressure of 3 atmosphere. Calculate the work done in -
55 L atm of work is obtained when 1.0 mole of an ideal gas is compressed isothermally from
a volume of 28.5 L to 18.5 L, the constant external pressure is
(A) 5.05 atm
(B) 5.5 atm
(C) 0.05 atm
(D) 0.55 atm
Absolute entropies of solids, liquids and gases can be determined by
- Measuring heat capacity of substance at various temperatures
- Subtracting standard entropy of reactants from products
- Measuring vibrational motion of molecules
- Using formula ΔS° = ST° - SO°
300 M mol of perfect gas occupies 13 L at 320 K. Calculate the work done in joules when the gas expands-
(a) isothermally against a Constant external pressure of 0.20atm.
(b) isothermal and reversible process.
(c) into vaccum until the volume of gas is increased by 3L (R=8.314J mol-1 K-1)