Advertisements
Advertisements
प्रश्न
For a certain reaction ΔH° = 219 kJ and ΔS° = –21 J/K. Determine whether the reaction is spontaneous or nonspontaneous.
Advertisements
उत्तर
Given:
∆H0 = 219kJ; ∆S0 = -21 J/K, ∆G0 = ?
For the standard state, T = 298 K
∆G0 = ∆H0 - T∆S0
= 219 - 298 × (-21) × 10-3
= 219 + 6.258
= 225.3 kJ
Since ∆S < 0 and ∆G0 > 0, the reaction is non-spontaneous.
APPEARS IN
संबंधित प्रश्न
Define entropy.
In which of the following, entropy of the system decreases?
Answer in brief.
What is entropy? Give its units.
Answer the following question.
Although ΔS for the formation of two moles of water from H2 and O2 is –327J K–1, it is spontaneous. Explain.
(Given ΔH for the reaction is –572 kJ).
Answer the following question.
Determine whether the following reaction is spontaneous under standard state conditions.
2H2O(l) + O2(g) → 2H2O2(l)
if ΔH° = 196 kJ, ΔS° = –126 J/K, does it have a cross-over temperature?
One mole of NaCl(s) on melting absorbed 30.5 kJ of heat and its entropy increased by 28.8 J K−1. The melting point of NaCl is ____________.
For a process, entropy change of a system is expressed as ________.
For the reaction:
\[\ce{2Cl_{(g)} -> Cl2_{(g)}}\]
Heat of combustion of C(s), H2(g) and C2H6(g) are −x1, −x2 and −x3 respectively. Hence heat of formation of C2H6(g) is ____________.
At what temperature, a chemical reaction will have the following values of ∆G, ∆S and ∆H?
∆G = −5.2 KJ mol−1, ∆H = 145.6 kJ mol−1, ∆S = −216 kJ mol−1
For a reaction to be non-spontaneous at all temperatures, values of ΔH and ΔS respectively are ____________.
If ΔH° and ΔS° for the reaction \[\ce{N2O_{4(g)} -> 2NO_{2(g)}}\] is 57.24 kJ and 175.8 JK-1 mol-1 respectively. What is the value of ΔG° for this reaction at 298 K?
Which of following is residual entropy of a substance?
Standard molar entropy is ______.
The equilibrium constant for a reaction is 10, value of ΔG° at 300 K is (R = 8 × 10-3 kJ)
For a reaction ΔH = - 30kJ and ΔS = - 45 JK-1, at what temperature reaction changes from spontaneous to non-spontaneous?
For which of the following reaction, ΔH = ΔU?
The criterion for a spontaneous process is ______.
Standard enthalpy and standard entropy changes for the oxidation of ammonia at 298 K are −382.64 kJ mol−1 and −145.6 JK−1 mol−1, respectively. Standard Gibb's energy change for the same reaction at 298 K is ______.
In which of the following reaction the value of Kp will be equal to Kc?
What is a spontaneous process? What are its characteristics?
Define second law of thermodynamics.
Which of the following is true about the decomposition of ozone?
