1 -Propanol and 2-propanol can be best distinguished by

Fehling solution is a weak oxidizing agent which can oxidize aliphatic aldehyde but not ketone.
Primary alcohols undergo oxidation with alkaline KMnO₄, acidic dichromate and conc. H₂SO₄ to give acids, whereas with Cu they give aldehydes.

$\begin{array}{l}\underset{\text{Propanol-1}}{{\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{OH}}\underset{\text{Heat}}{\overset{\mathrm{Cu}}{\to }}\underset{\begin{array}{l}\text{ Propanal}\\ \left(\text{responds Fehling solution}\right)\end{array}}{{\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{CHO}}\\ \underset{\text{Propanol-2}}{{\mathrm{CH}}_3{\mathrm{CHOHCH}}_3}\to \underset{\begin{array}{l}\text{ Propanone}\\ \left(\text{negative Fehling solution}\right)\end{array}}{{\mathrm{CH}}_3{\mathrm{COCH}}_3}\end{array}$