Question

In the Arrhenius equation $K=A{e}^{-Ea/RT}$ the rate constant k equal to the Arrhenius constant (A) when:

• A. the temperature becomes infinite
• B. 50% reactants are converted to product
• C. the fraction of the molecules crossing the the energy barrier is unity
• D. the is no need of activation energy to reactants for undergoing chemical change

Answer 1

Answer: (A), (C), (D)

the temperature becomes infinite
the fraction of the molecules crossing the the energy barrier is unity
the is no need of activation energy to reactants for undergoing chemical change

$k=A.e^{-E_a/RT}$

For $K=A,$ the temperature should be infinity, $T⟶\infty$

$\therefore \frac{1}{T}⟶0\therefore \frac{{-E}_a}{RT}⟶0\therefore K=A$

No need of activation energy to reactants for undergoing chemical charge i.e. $E_a=0\Rightarrow e°=1K=A$

The fraction of molecules crossing the energy barrier should be unity. $i.e.\frac{E_a}{RT}=0\Rightarrow e°=1K=A$