Write the balanced chemical equation for the reaction of ethene with hypobromous acid and its oxidation with potassium tetraoxomanganate(VII).

Ethene ($\text{CH}_2=\text{CH}_2$) reacts with hypobromous acid ($\text{HOBr}$) in an electrophilic addition reaction. The double bond breaks, and the -OH and -Br groups add across the carbon atoms.

The product formed is 2-bromoethanol.

2. Oxidation of Ethene with Potassium Tetraoxomanganate(VII)

Ethene ($\text{CH}_2=\text{CH}_2$) is oxidized by nascent oxygen ($[\text{O}]$) from dilute, cold potassium tetraoxomanganate(VII) ($\text{KMnO}_4$) in the presence of water ($\text{H}_2\text{O}$). This reaction is known as Baeyer's test and results in the formation of a diol.

The product is ethane-1,2-diol (also known as ethylene glycol).

3. Definition of Polymerisation Reaction

Polymerisation is a chemical process in which many small, repeating molecules, called monomers, react together to form a very large chain-like molecule, known as a polymer.

During polymerisation, the monomers link together through covalent bonds, forming a macromolecule with repeating structural units.

The definition is:
A polymerisation reaction is a chemical process where numerous small molecules, called monomers, combine to form a large, chain-like molecule known as a polymer. The monomers link together through covalent bonds to create a repeating structural unit within the polymer.