1
AIEEE 2008
+4
-1
Standard entropy of X2, Y2 and XY3 are 60, 40 and 50 JK−1 mol−1 , respectively. For the reaction,
$${1 \over 2} X_2$$ + $${3 \over 2} Y_2 \to$$ XY3, $$\Delta H$$ = -30 kJ, to be at equilibrium, the temperature will be :
A
1250 K
B
500 K
C
750 K
D
1000 K
2
AIEEE 2007
+4
-1
In conversion of lime-stone to lime,
CaCO3(s) $$\to$$ CaO(s) + CO2 (g) the vales of ∆H° and ∆S° are +179.1 kJ mol−1 and 160.2 J/K respectively at 298 K and 1 bar. Assuming that ∆H° do not change with temperature, temperature above which conversion of limestone to lime will be spontaneous is :
A
1008 K
B
1200
C
845 K
D
1118 K
3
AIEEE 2007
+4
-1
Identify the correct statement regarding a spontaneous process :
A
For a spontaneous process in an isolated system, the change in entropy is positive
B
Endothermic processes are never spontaneous
C
Exothermic processes are always spontaneous
D
Lowering of energy in the reaction process is the only criterion for spontaneity
4
AIEEE 2007
+4
-1
Assuming that water vapour is an ideal gas, the internal energy change $$\left( {\Delta U} \right)$$ when $$1$$ mol of water is vapourised at $$1$$ bar pressure and $${100^ \circ }C$$ (Given : molar enthalpy of vapourisation of water at $$1$$ bar and $$373$$ $$K$$ $$= 41\,kJ\,mo{l^{ - 1}}\,$$
and $$R = 8.3\,J\,mo{l^{ - 1}}\,{K^{ - 1}}$$ )
A
$$41.00\,kJ\,mo{l^{ - 1}}$$
B
$$4.100\,kJ\,mo{l^{ - 1}}$$
C
$$3.7904\,kJ\,mo{l^{ - 1}}$$
D
$$37.904\,kJ\,mo{l^{ - 1}}$$
EXAM MAP
Medical
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