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Byju's Answer

Standard IX

Chemistry

Temperature and Rate of Reaction

If the activa...

Question

If the activation energy of a reaction is 80.9 kJ $m o l^{- 1}$ , the fraction of molecules at 700 K, having enough energy to react to form products is $e^{- x}$ . The value of x is_____. (Rounded off to the nearest integer)

[Use $R = 8.31 J K^{- 1} m o l^{- 1}$ ]

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Solution

$E_{a} = 80.9 k J / m o l$
Fraction of molecules able to cross energy barrier = $e^{- E a / R T} = e^{- x}$

$x = \frac{E_{a}}{R T} = \frac{80.9 \times 1000}{8.31 \times 700} = 13.91$

$x \approx 14$

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If the activation energy of a reaction is 80.9 kJ $m o l^{- 1}$ , the fraction of molecules at 700 K, having enough energy to react to form products is $e^{- x}$ . The value of x is_____. (Rounded off to the nearest integer)

[Use $R = 8.31 J K^{- 1} m o l^{- 1}$ ]

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