An ideal gas expands in volume from 10-3 m3 to 10-2 m3 at 300 K against a constant pressure of 105 Nm-2.
The work done is
800 kJ
900 kJ
270 kJ
-900 J
When the heat of a reaction at constant pressure is -2.5 × 103 cals and entropy change for the reaction is 7.4 cal deg -1, it is predicted that the reaction at 25ºC is
reversible
spontaneous
non - spontaneous
irreversible
A gas present in a cylinder, fitted with a frictionless piston, expands against a constant pressure of 1 atm from a volume of 2 liter to a volume of 6 liter. In doing so, it absorbs 800 J heat from surroundings. The increase in internal energy of process is
305.85 J
394.95 J
405.83 J
-463.28 J
The heat of sublimation of iodine is 24 cal g-1 at 50oC. If specific heat of solid iodine and its vapours are 0.055 and 0.031 cal g-1 respectively, the heat of sublimation of iodine at 100oC is
22.8 cal g-1
25.2 cal g-1
-22.8 cal g-1
-25.2 cal g-1
In which case, a spontaneous reaction is possible at any temperature?
∆H –ve, ∆S +ve
∆H –ve, ∆S –ve
∆H +ve, ∆S +ve
None of these.
The Van’t Hoff reaction isotherm is
∆G = RT log Kp
–∆G = RT In Kp
∆G = RT2 In Kp
None of these
The value of log10 K for a reaction A B is
(Given, ∆rHo298 K = - 54.07 kJ mol -1
∆rSo298 k = 10 JK -1 mol -1
and R = 8.314 JK -1 mol -1
= 2.303 x 8.314 x 298
= 5705
5
10
95
100
In which process net work done is zero?
Cyclic
Isobaric
Adiabatic
Free expansion
For a reaction
∆H = 30 kJ mol -1 and ∆S = 0.07 kJ K -1 mol -1 at 1 atm. The temperature up to which the reaction would not be spontaneous is
T < 400.08 K
T < 273.15 K
T < 428.57 K
T < 473.50 K
In conversion of limestone to lime,
CaCO3 (s) → CaO(s) + CO2 (g)
The value of ∆Ho and ∆So are +179.1 kJ mol -1 and 160.2 J/ K respectively at 298 K and 1 bar. Assuming that ∆Ho and ∆So do not change with temperature, temperature above which conversion of limestone to lime will be spontaneous is
1008 K
1200 K
845 K
1118 K
