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The heat of combustion of solid benzoic acid at constant volume is -321.30 kJ at 27 C. The heat of combustion at constant pressure is (-321.30 - xR) kJ, the value of x is .
150
C6H5COOH(s) + 152O2(g) 7CO2(g) + 3H2O(l)
ng = 7 - 152 = - 12 (only gases counted)
H = U + ngRT
= -321.30 + (- 12 ) R 300
= -321.30 - 150R ⇒ x = 150
Answer: 150
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The enthalpy of formation of ethane (C2H6) from ethylene by addition of hydrogen where the bond-energies of C-H, C-C, C=C, H-H are 414 kJ, 347 kJ, 615 kJ and 435 kJ respectively is − kJ
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Choose the correct option for free expansion of an ideal gas under adiabatic condition from the following :
For a certain reaction at 300 K, K = 10, then for the same reaction is − 10-1 kJ mol-1. (Given R = 8.314 J K-1 mol-1)
Consider the following reaction at 298 K: 32O2(g) O3(g); KP = 2.47 10-29. rG for the reaction is kJ. (Given R = 8.314 JK-1 mol-1)
If 5 moles of an ideal gas expands from 10 L to a volume of 100 L at 300 K under isothermal and reversible condition then work, w, is −x J. The value of x is . (Given R = 8.314 J K-1 mol-1)
[figure] An ideal gas undergoes a cyclic transformation starting from the point A and coming back to the same point by tracing the path A B C A as shown in the diagram above. The total work done in the process is J.
Two reactions are given below: 2Fe(s) + 32O2(g) Fe2O3(s), H = -822 kJ/mol C(s) + 12O2(g) CO(g), H = -110 kJ/mol Then enthalpy change for following reaction 3C(s) + Fe2O3(s) 2Fe(s) + 3CO(g) is kJ/mol.
Which of the following is not correct?