Rate law for the reaction,

$$ \mathrm{C}_2 \mathrm{H}_5 \mathrm{I}_{(\mathrm{g})} \longrightarrow \mathrm{C}_2 \mathrm{H}_{4(\mathrm{~g})}+\mathrm{HI}_{(\mathrm{g})} \text { is } \mathrm{r}=\mathrm{k}\left[\mathrm{C}_2 \mathrm{H}_5 \mathrm{I}\right] $$

What is the order and molecularity of this reaction?

Find the mass of potassium chlorate required to liberate $5.6 \mathrm{dm}^3$ of oxygen gas at STP? (molar mass of $\mathrm{KClO}_3=122.5 \mathrm{~g} / \mathrm{mol}$ )

Which of the following reactions exhibits decrease in entropy?

What is the wavenumber of the photon emitted during transition from the orbit $\mathrm{n}=5$ to that of $\mathrm{n}=2$ in hydrogen atom? $\left[\mathrm{R}_{\mathrm{H}}=109677 \mathrm{~cm}^{-1}\right]$