Chemistry 2nd Paper MCQ-Dhaka Board-2021

1. Propyne$+\mathrm{H}_{2} \xrightarrow{A}$ propene; $A$ is -

2. Which compound will produce when propanal is reduced by $\mathrm{Zn}-\mathrm{Hg}$ and cons. $\mathrm{HCl}$ ?

3. Which one is the nucleophile?

4. The standard oxidation potential of $\mathrm{Li}$, $\mathrm{Na}, \mathrm{Zn}$ and $\mathrm{Cu}$ is $+\mathbf{3 . 0 4} \mathrm{V},+2.71 \mathrm{~V}$, $+0.76 V$ and $-0.34 V$ respectively, which cation will charge free at first during electrolysis?

5. $\mathrm{H}_{2} \mathrm{O}+\mathrm{HCl} \rightarrow \mathrm{Cl}^{-1}+\mathrm{H}_{3} \mathrm{O}^{+}$, in this reaction -
i. $\mathrm{Cl}^{-1}$ is the conjugate base of $\mathrm{HCl}$

ii. $\mathrm{H}_{2} \mathrm{O}$ is an acid

iii. $\mathrm{H}_{3} \mathrm{O}^{+}$is a conjugate acid

Which one is correct?