What are isomers?
(b) Two compounds have the same molecular formula $C_3{H}_{6}O.$ Identify the name of the compounds and write their structural formula.
(c) Mentions the steps involved in bringing the following conversion.
(i) Ethanol to ethene
(ii) Propanol to propanoic acid
 

(a) A compound having the same molecular formula but different physical and chemical properties are called an isomer, and this phenomenon is known as isomerism.
(b) Acetone IUPAC name: propanone, $\left(C{H}_{3}COC{H}_3\right)$and propanal $\left(C{H}_{3}C{H}_{2}CHO\right)$ are two compounds that have the same molecular formula $C_3{H}_{6}O.$ The name of these compounds and their structural formula are;

(c) Conversion of;
(i) Ethanol to ethene:
Heating ethanol with an excess of concentrated sulphuric acid at about ${170}^{\circ }C$ gives ethene, the process of the dehydration process. The chemical reaction follows;

(ii) Propanol to propanoic acid In the chemical reaction of the conversion of propanol to propanoic acid, propanol gets oxidized to propanoic acid in the presence of alkaline potassium permanganate. The chemical reaction is as follows;