Lucas test is used to distinguish between primary, secondary and tertiary alcohols A mixture of conc $HCl$+ anhy $ZnCl_{2}$ is called Lucas reagent. In Lucas test tertiary alcohols immediately give turbidity while secondary alcohols give turbidity after $5$ min. Primary alcohols give no reaction with Lucas reagent at room temperature
$\underset{\text{(Primary alcohol)}}{{CH_{3}OH / CH_{3}CH_{2}OH}}\ce{ ->[conc\, HCl+anhy\, ZnCl_{2}] }$ No
reaction and hence, no white cloudiness on turbidity at room temperature
$\underset{\text{(Secondary alcohol)}}{{(CH_{3})_{2}CHOH}} \ce{ ->[conc\, Hcl + anhy \,ZnCl_{2}] }$
White cloudiness or turbidity appears with in about $5$ min
$\underset{\text{(turboidityalcohol}}{{(CH_{3})_{3}COH}}\ce{ ->[conc \, HCl \,+ anhy \, ZnCl_{2}] }$
White cloudiness or turbidity appears immediately