Considering entropy(s) as a thermodynamic parameter, the criterion for the spontaneity of any process, the change in entropy is
C.
According to law of entropy (also known as second law of thermodynamics), the entropy for a spontaneity of any process is always accompained by an increase in total entropy of universe, i.e.
Standard enthalpy (heat) of formation of liquid water at 25°C is around
H2(g) + O2(g) → H2O (l)
-237 kJ/mol
237 kJ/mol
- 286 kJ/mol
286 kJ/mol
Given ΔHf° for CO2(g) , CO(g) and H2O(g) are -393.5, -110.5 and -241.8 kJ mol-1, respectively. The ΔHf° [in kJ mol-1] for the reaction
CO2(g) + H2(g) → CO(g) + H2O (g) is
524.1
-262.5
-417
412
For silver, CP( K-1 mol-1) = 23 + 0.01T. If the temperature (T) of 3 moles of silver is raised from 300 K to 1000 K at 1 atm pressure, the value of H will be close to :
21 kJ
62 kJ
16 kJ
13 kJ
During compression of a spring the work done is 10 kJ and 2 kJ escaped to the surroundings as heat. The change in internal energy, U (in kJ) is:
-12
8
12
-8
Consider the given plot of enthalpy of the following reaction between A and B. A + B → C + D. Identify the incorrect statement.
C is the thermodynamically stable product.
Formation of A and B from C has highest enthalpy of activation.
Activation enthalpy to form C is 5 kJ mol-1 less than that to form D.
D is kinetically stable product.
5 moles of an ideal gas at 100 K are allowed to undergo reversible compression till its temperature becomes 200 K. If CV = 28 J K–1 mol–1, calcuIate ΔU and ΔPV for this process. ( R= 8.0 JK-1 mol-1 )
ΔU = 14kJ; Δ(pV) = 18kJ
ΔU = 14kJ; Δ(pV) = 0.8J
ΔU = 14kJ; Δ(pV) = 4kJ
ΔU = 2.8kJ; Δ(pV) = o.8J
Among the following, the set of parameters that represents path functions, is:
(A) q+w
(B) q
(C) w
(D) H-TS
A, B and C
B, C and D
B and C
A and D
A process will be spontaneous at all temperatures if :
ΔH <0 and ΔS <0
ΔH <0 and ΔS >0
ΔH >0 and ΔS >0
ΔH >0 and ΔS <0
The standard Gibbs energy for the given cell reaction in kJ mol-1 at 298 K is:
Zn (s) + Cu2+ (aq) → Zn2+ (aq) + Cu (s), E° = 2V at 298 K
-192
384
-384
192