What is the compound $D$ in the following reaction sequence?
$CH_3CH_2OH$ $\xrightarrow{P + I_2} A$ $\xrightarrow{Mg} B$ $\xrightarrow{HCHO} C$ $\xrightarrow{H_2O} D$

Which of the following is the correct decreasing order of ease of acid-catalyzed esterification of alcohols?

Identify the structure of the product formed in the following reaction of $4-$chloro$-4-$methylpentan$-1-$ol in a neutral polar medium:
$(CH_3)_2C(Cl)CH_2CH_2CH_2OH \to HCl + C_6H_{12}O$

$A$ sample of $4.5 \ g$ of an unknown monohydric alcohol,$ROH$,was added to methylmagnesium iodide. $A$ gas is evolved,collected,and its volume is measured to be $3.1 \ L$ at $NTP$. The molecular weight of the unknown alcohol is $g/mol$. [Nearest integer]

Identify $Z$ in the following reaction sequence:
$C_2H_5OH$ $\xrightarrow{PBr_3} X$ $\xrightarrow{KOH(alc.)} Y$ $\xrightarrow[(ii) H_2O, \Delta]{(i) H_2SO_4} Z$

The alcohol that produces turbidity immediately with $ZnCl_2 +$ conc. $HCl$ at room temperature is: