Question

In Lucas test an alcohol react immediately and gives insoluble chloride. The alcohol is

• A. $CH_{3}OH$
• B. $CH_{3}CH_{2}OH$
• C. $(CH_{3})_{2}CHOH$
• D. $(CH_{3})_{3}COH$

Answer 1

Answer: (D)

$(CH_{3})_{3}COH$

Answer 2

In Lucas test, alcohol reacts with cone. $H C l$ in anhy $Z n C l_{2}$ and convert into alkyl halide, which is insoluble in water and their appearance is indicated by the appearance of turbidity. Since, the order of reactivity of alcohol is tertiary $>$ secondary $>$ primary Hence, the Lucas test is immediately given by tertiary alcohol, ie, $\left( CH _{3}\right)_{3} COH$.