Question

Phenol can be distinguished from ethanol by the following reagents, except:

• A. Sodium
• B. Neutral $FeC{l}_3$
• C. Phthalic anhydride/conc. $H_{2}S{O}_4$ and $NaOH$
• D. $B{r}_2/H_{2}O$

Answer 1

Answer: (A)

With neutral $FeC{l}_3$ solution, phenol gives violet colour solution but $6C_6{H}_{5}Oh+FeC{l}_3\to \underset{\text{Violet colour compl,ex}}{[FeO(C_6{H}_5{)}_6{]}^{3-}}+3H^{+}+3HCl$
Phthalic anhydride/Conc. ${\text{H}}_{\text{2}}{\text{SO}}_{\text{4}}$ and $\text{NaOH}$


Phenol cannot be distinguished from ethanol by sodium because both evolve hydrogen with sodium.
$2C_6{H}_{5}OH+2Na\to 2C_6{H}_{5}ONa+H_2\uparrow$
$2C_2{H}_{5}OH+2Na\to 2C_2{H}_{5}ONa+H_2\uparrow$