1
JEE Main 2024 (Online) 29th January Morning Shift
Numerical
+4
-1

For a reaction taking place in three steps at same temperature, overall rate constant $$\mathrm{K}=\frac{\mathrm{K}_1 \mathrm{~K}_2}{\mathrm{~K}_3}$$. If $$\mathrm{Ea}_1, \mathrm{Ea}_2$$ and $$\mathrm{Ea}_3$$ are 40, 50 and $$60 \mathrm{~kJ} / \mathrm{mol}$$ respectively, the overall $$\mathrm{Ea}$$ is ________ $$\mathrm{kJ} / \mathrm{mol}$$.

2
JEE Main 2024 (Online) 27th January Evening Shift
Numerical
+4
-1

Time required for completion of $$99.9 \%$$ of a First order reaction is ________ times of half life $$\left(t_{1 / 2}\right)$$ of the reaction.

3
JEE Main 2024 (Online) 27th January Morning Shift
Numerical
+4
-1

Consider the following data for the given reaction

$$2 \mathrm{HI}_{(\mathrm{g})} \rightarrow \mathrm{H}_{2(\mathrm{~g})}+\mathrm{I}_{2(\mathrm{~g})}$$

The order of the reaction is _________.

4
JEE Main 2023 (Online) 15th April Morning Shift
Numerical
+4
-1
For a reversible reaction $\mathrm{A} \rightleftharpoons \mathrm{B}$, the $\Delta \mathrm{H}_{\text{forward reaction}} = 20 \mathrm{~kJ} \mathrm{~mol}^{-1}$. The activation energy of the uncatalysed forward reaction is $300 \mathrm{~kJ} \mathrm{~mol}^{-1}$. When the reaction is catalysed keeping the reactant concentration same, the rate of the catalysed forward reaction at $27^{\circ} \mathrm{C}$ is found to be same as that of the uncatalysed reaction at $327^{\circ} \mathrm{C}$.

The activation energy of the catalysed backward reaction is ___________ $\mathrm{kJ}~ \mathrm{mol}^{-1}$.