Answer to Question #134122 in General Chemistry for Kabibe Alexander

Question

When I place bleach on my coloured clothes they get discoloured. Help me understand why this happens. Is this an oxidation-reduction reaction?

Answer 1

QUESTION # 134122

When I place bleach on my coloured clothes they get discoloured. Help me understand why this happens. Is this an oxidation-reduction reaction?

ANSWER

Calcium hypochlorite and sodium hypochlorite (bleaches) reacts with water according to the equations;

Ca(OCl)₂ + 2H₂O –> 2HOCl + Ca²⁺ + 2OH^-

NaOCl + H₂O –> HOCl + Na⁺ + OH^-

Bleaching process of bleaching agents

Reason to bleaching property is hypochlorite ion (OCl^-). Colourful things are oxidized by atomic oxygen (‘O’) which is formed by OCl^- ion (bleached). Atomic oxygen is very reactive.

2HOCl –> H₂O + Cl₂ + ‘O’

‘O’ + 2e –> O^2- (Reduction)

when atomic oxygen is reduced, Colorful things are oxidized simultaneously. The reaction is therefore oxidation-reduction reaction.