Explain the process of obtaining alcohols from aldehydes and ketones with examples.

(N/A) Preparation: Aldehydes and ketones undergo reduction to their corresponding alcohols by the addition of hydrogen in the presence of catalysts. This process is known as catalytic hydrogenation of aldehydes and ketones.
$(b)$ Catalysts: Finely divided metals such as platinum $(Pt)$,palladium $(Pd)$,or nickel $(Ni)$ are generally used for this reduction. Sodium borohydride $(NaBH_4)$ or lithium aluminium hydride $(LiAlH_4)$ can also be used to convert aldehydes and ketones into alcohols.
$(c)$ General Reaction: Aldehydes yield primary alcohols,and ketones yield secondary alcohols.
$(d)$ Examples:
$CH_3CHO + H_2 \xrightarrow{Pd/Pt} CH_3CH_2OH$
$C_6H_5CHO + H_2 \xrightarrow{Pd/Pt} C_6H_5CH_2OH$
$CH_3COCH_3 + H_2 \xrightarrow{NaBH_4} CH_3CH(OH)CH_3$
$C_6H_5COCH_3 + H_2 \xrightarrow{LiAlH_4} C_6H_5CH(OH)CH_3$