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कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

The activation energy for the reaction 2HIA(g)⟶HA2A(g)+IA2A(g) is 209.5 kJ mol−1 at 581K. Calculate the fraction of molecules of reactants having energy equal to or greater than activation energy? - Chemistry

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प्रश्न

The activation energy for the reaction \[\ce{2 HI_{(g)} -> H2_{(g)} + I2_{(g)}}\] is 209.5 kJ mol−1 at 581K. Calculate the fraction of molecules of reactants having energy equal to or greater than activation energy?

संख्यात्मक
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उत्तर

In the given case:

Ea = 209.5 kJ mol−1 

T = 581 K

R = 8.314 JK−1 mol−1

Now, the fraction of molecules of reactants having energy equal to or greater than activation energy is given as:

x = `"n"/"N"`

x = `e^((-E_a)/"RT")`

In x = `- (E_a)/"RT"`

or, log x = `-E_a/(2.303  "RT")`

or, log x = `-(209.5 xx 10^3  "J mol"^-1)/(2.303 xx 8.314  "JK"^-1  "mol"^-1 xx 581  "K")`

= −18.8323

x = antilog (−18.8323)

= antilog 19.1677

= 1.471 × 10−19

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पाठ 3: Chemical Kinetics - Intext Questions [पृष्ठ ८४]

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एनसीईआरटी Chemistry Part 1 and 2 [English] Class 12
पाठ 3 Chemical Kinetics
Intext Questions | Q 3.9 | पृष्ठ ८४

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