Heating $I_2$ and $NaOH$ with which of the following produces iodoform?

$CH_2 = CH_2$ $\xrightarrow{HBr} X$ $\xrightarrow{\text{Hydrolysis}} Y$ $\xrightarrow[I_2 \text{ excess}]{Na_2CO_3} Z$. What is $Z$ in the given reaction?

Which alcohol produces turbidity with Lucas reagent after five minutes $:-$

The boiling point of glycerol is higher than that of propanal because of:

The major product of the following reaction is:

Propene is the product obtained by the dehydrogenation of