MCQ
Addition of cold conc. $\mathrm{H}_2 \mathrm{SO}_4$ with alkenes is an example of :
- AElectrophilic substitution reaction.
- BNucleophilic substitution reaction.
- ✓Electrophilic addition reaction.
- DNucleophilic addition reaction.
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$CO + \frac{1}{2}{O_2} \to C{O_2};\,\Delta H = - 24\,kJ$ The heat of formation of $C{O_2}$ is .....$kJ$
[Given : $pKa$ (acetic acid) $=4.74$ ]
$(A)$ In $B _{2} H _{6}$, all $B - H$ bonds are equivalent.
$(B)$ In $B _{2} H _{6}$ there are four $3-$centre$-2-$electron bonds.
$(C)$ $B _{2} H _{6}$ is a Lewis acid.
$(D)$ $B _{2} H _{6}$ can be synthesized form both $BF _{3}$ and $NaBH _{4}$.
$(E)$ $B _{2} H _{6}$ is a planar molecule.
Choose the most appropriate answer from the options given below..... .
