हिंदी

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,

Advertisements
Advertisements

प्रश्न

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?

एक पंक्ति में उत्तर
Advertisements

उत्तर

When ∆H positive and ∆S is negative, then ∆G is positive regardless of temperature. Hence, the reaction is nonspontaneous at all temperatures. It does NOT have a cross-over temperature.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 4: Chemical Thermodynamics - Exercises [पृष्ठ ८८]

APPEARS IN

बालभारती Chemistry [English] Standard 12 Maharashtra State Board
अध्याय 4 Chemical Thermodynamics
Exercises | Q 4.11 | पृष्ठ ८८

संबंधित प्रश्न

In which of the following, entropy of the system decreases?


Answer the following in one or two sentences.

State whether ΔS is positive, negative or zero for the reaction 2H(g)  →  H2(g). Explain.


Answer the following in one or two sentences.

State second law of thermodynamics in terms of entropy.


Answer the following in one or two sentences.

If the enthalpy change of a reaction is ∆H how will you calculate the entropy of surroundings?


Answer the following in one or two sentences.

Comment on the spontaneity of reactions for which ∆H is positive and ∆S is negative.


Obtain the relationship between ∆G° of a reaction and the equilibrium constant.


For a certain reaction ΔH° = 219 kJ and ΔS° = –21 J/K. Determine whether the reaction is spontaneous or nonspontaneous.


Equilibrium constant for a reaction is 20. What is the value of ΔG° at 300 K? (R = 8 x 10-3 kJ)


A system is changed from an initial state to a final state by a manner such that ∆H = Q. If the change from initial state to final state was made by a different path, then ____________.


For a reversible spontaneous change, ∆S is ____________.


Arrange the following in order of increasing entropy.

I. 1.0 mol H2O (298 K, 1 atm)

II. 1.0 mol H2O (270 K, 1 atm)

III. 1.0 mol H2O (400 K, 1 atm)


In how many of the following, ∆S is positive?

i. Melting of ice

ii. Sublimation of iodine

iii. Dissolution of CuSO4 in water

iv. Condensation of water vapour

v. Dissociation of H2 molecule into atoms

vi. Conversion of carbon dioxide gas to dry ice

vii. Vaporization of acetone


In which of the following, ∆S is positive?


For the reaction:

\[\ce{2Cl_{(g)} -> Cl2_{(g)}}\]


Which one of the following has ΔS0 greater than zero?


Equilibrium constant for a reaction is 20. What is the value of ∆G0 at 300 K? (R = 8 × 10−3 kJ)


For a reaction to be non-spontaneous at all temperatures, values of ΔH and ΔS respectively are ____________.


Calculate the amount of heat liberated during formation of 2. 7 kg of water if heat of formation of water is - 284.5 kJ mol-1.


When will be change in Gibb's free energy always negative?


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 ______.


Dinitrogen and dioxygen combined to form nitrous oxide in equilibrium at 850 K. The equilibrium constant for this reaction is 0.56. If the equilibrium concentration of nitrous oxide gas is 3 × 10-3 M and both dinitrogen and dioxygen have the same concentration, then what will be the concentration of dinitrogen gas in M?


Identify whether the following pair have larger entropy or not. If yes then Why?

He(g) in a volume of 1 L or He(g) in a volume of 5 L both at 25°C.


Identify whether the following pair have a larger entropy or not. If yes then Why?

C2H5OH(l) or C2H5OH(g)


What is a spontaneous process? What are its characteristics?


ΔH for the reaction is − 110 kJ, and ΔS is + 40 JK−1 at 400 K. The free energy change for the reaction is ______.


The entropy of vaporisation of benzene is 85 J K−1 mol−1. When 117 g of benzene vaporises at its boiling point, what is the entropy change of the surroundings if the process is at equilibrium?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×