- AReaction mechanisms are studied using isotopic labelling.
- BIsolation of reactive intermediates is a method to establish reaction mechanism.
- CBoth a and b are correct.
- DNeither a nor b is correct.
Explanation:
Both a and b are correct.
CH3−CO−O*H + CH3−OH $\xrightarrow{\text{H}^+}$ CH3−COO−CH3 + H2O*
In the above reaction, O atom of −OH group of acetic acid is labelled. It is then observed that labelled O atom is found in water. Hence, we can conclude that
−OH group of acetic acid combines with H atom of methanol.
Consider the conversion A → D.
It can proceed through following two different mechanisms.
A → B → D.
A → C → D.
Suppose that we are able to isolate intermediate B but we cannot isolate intermediate C. Hence, we can say that the reaction mechanism is A → B → D.
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$\mathrm{Ph}-\mathrm{CH}=\mathrm{CH}_2 \xrightarrow[\text { (iii) } \mathrm{HBr}{(iv) \mathrm{Mg}, ether, then \mathrm{HCHO} / \mathrm{H}_3 \mathrm{O}^{+}}]{{(i)BH_3}{\text { (ii) } \mathrm{H}_2 \mathrm{O}_2,{ }^{\text {(-) }} \mathrm{OH}}} \mathrm{A}$
