Question

The alcohol that produces turbidity immediately with $Zn{Cl}_2/conc.HCl$ at room temperature is:

• A. 1-hydroxy butane
• B. 2-hydroxy butane
• C. 2-hydroxy-2-methyl propane
• D. 1-hydroxy-2-methyl propane

Answer 1

The correct option is C 2-hydroxy-2-methyl propane

Mixture of anhydrous $Zn{Cl}_2$ and $conc.HCl$ is known as Lucas reagent. Lucas test is used for the distinction between primary, secondary and tertiary alcohols.
The tertiary alcohol reacts immediately with Lucas reagent producing turbidity.
The secondary alcohol gives turbidity within $5-10min$ and primary alcohol do not give turbidity at all at room temperature. In the given alternates, 2-hydroxy-2-methyl propane is $3$ alcohol, so it is more reactive.