$CH_3-CH(OH)-CH_2-CHO$
$3HCHO + A \xrightarrow[40^o C]{Na_2CO_3} (B) (82\%)$
Product $(B)$ of the above reaction is

Which of the following will fail to react with potassium dichromate and dilute sulphuric acid?

Which of the following compounds would not give tert-butyl alcohol when treated with excess methylmagnesium bromide $(CH_3MgBr)$ followed by acid?

Which one among the following compounds will most readily be dehydrated under acidic condition?

The correct order of reactivity of $PhMgBr$ with:
$(I)$ $Ph-CO-Ph$
$(II)$ $CH_3-CHO$
$(III)$ $CH_3-CO-CH_3$
is:

$A$ compound $(X)$ possesses a smell like bitter almond.
$(i)$ It does not give the Fehling test.
$(ii)$ It gives the silver mirror test.
$(iii)$ Compound $(X)$ gives orange precipitates of benzaldehyde $2,4-$dinitrophenylhydrazone with $2,4-DNP$.
Identify compound $(X)$ and provide its chemical reactions.