Question

The standard molar entropy of benzene is 173.3 J/K-mol. Calculate the change in its standard molar Gibbs energy when benzene is heated from 25C to 45C.

Answer #1

**Solution :-**

Standard molar enthalpy of the benzene = 49000 J/mol

Standard lets calculate the free energy at the 25 C = 298 K

and 45 C = 318 K

Delta G = Delta H - T*delta S

= 49000 J - (298*173.3 J per mol K)

= -2643.4 J /mol

Delta G = 49000 J per mol - (173.3 J per mol K * 318 K)

= -6109.4 J per mol

so the change in the free energy is = -61.09.4 J - (-2643.4 J) = -3466 J

-3466 J * 1 kJ / 1000 J = -3.466 kJ

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is 29.1 J/(mol-K) .)

Calculate the change in entropy (in J/K) when 52.8 g of nitrogen
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Calculate the standard molar Gibbs free energy change
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3 C2H4(g) ®
C6H6(g) + 3 H2(g).

calculate the molar entropy change when (a) water and (b)
benzene are evaporated at their boiling points at a pressure of 1
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HgO(s)
Hg(g)
O2(g)
Enthaply Delta H kj/mol
-90.8
61.3
Entropy Delta S j/mol. K
70.3
174.9
205.0
Above is a table of thermodynamics date for the chemical species
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A) Calculate the molar entropy of reaction at 25 C
B) Calculate the standard Gibbs free enregy of the reaction at
25 C given that the enthaply of reaction at 25 C is 304.2
Kj/mol
C)Calculate the equilibrium constant for the reaction...

Trouton’s rule states that the entropy of boiling at the normal
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Does the Delta vapS for H2O at its normal boiling point support
Trouton’s rule? Can you explain any deviation? (c) Predict the
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Calculate the standard entropy change for the reaction:
2H2S(g) +SO2(g)→3Srh(s)
+2H2O(g), where:
1. S0[Srh]=32 J/k mol
2. S0[H2O(g)]=189 J/k mol
3. S0[H2S(g)]=206 J/k mol
4. S0[SO2]=248 J/k mol
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b. -1134 J/K
c. -186 J/K
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