For the given reaction
$R_1-C(R)(X)-R_2 \xrightarrow{HOH} R_1-C(R)(OH)-R_2$
Which substrate will give maximum racemisation?

Which of the following compounds will show retention in configuration on nucleophilic substitution by $OH^{-}$ ion?

The hybridization state of carbon atoms in the product formed by the reaction of ethyl chloride with aqueous potassium hydroxide is

Among the following pairs of reactions,in which pair is the second reaction more reactive than the first in an $S_{N^1}$ reaction?

Observe the following reactions. The order of reactivity of $x, y, z$ towards $S_{N}1$ reaction is:

Arrange the following compounds in order of decreasing rate of hydrolysis for $S_{N}1$ reaction:
$(I) \ C_6H_5-CH_2-Br$
$(II) \ p-CH_3-C_6H_4-CH_2-Br$
$(III) \ p-CH_3CH_2-C_6H_4-CH_2-Br$
$(IV) \ p-(CH_3)_2CH-C_6H_4-CH_2-Br$