Question

Write the structural formulae of probable isomeric alcohols having molecular formula ${{C}_{4}}{{H}_{10}}O$. What is the action of sodium-amalgam and water on ethyl methyl ketone?

Answer 1

Hint: A structural isomer of a compound is another compound whose molecule has the same number of atoms of each element, but with logically distinct bonds between them. The term metamer was formerly used for the same concept.

Complete solution:
Isomers are molecules or polyatomic ions with identical molecular formulas — that is, the same number of atoms of each element — but distinct arrangements of atoms in space. Isomerism is the existence or possibility of isomers. Isomers do not necessarily share similar chemical or physical properties.
The probable isomers of alcohols having molecular formula ${{C}_{4}}{{H}_{10}}O$ are four i.e. 2-butanol, 1-butanol, 2-methyl-2-propanol, and 2-methyl-1-propanol.The structure of isomers are as follows:

Ketones reduces to corresponding secondary alcohol by the action of nascent hydrogen supplied by sodium amalgam and water.

Aldehydes and ketones are most readily reduced with hydride reagents. The reducing agents $LiAl{H_4}$ and $NaB{H_4}$ act as a source of hydride ions.

Note: Sodium amalgam, commonly denoted $Na(Hg)$, is an alloy of mercury and sodium. The term amalgam is used for alloys, intermetallic compounds, and solutions (both solid solutions and liquid solutions) involving mercury as a major component. Sodium amalgams are often used in reactions as strong reducing agents with better handling properties compared to solid sodium. They are less dangerously reactive toward water and in fact are often used as an aqueous suspension.