KITCHEN SINK CHEMICALS EXPLAINED

Every home has an armoury of liquids to combat stains and leave surfaces germ-free. But how do they do their job?

- MIKE BEDFORD

BLEACH

THE STAIN REMOVER

Bleach is a general-purpose cleaning product that disinfects and removes colour from organic stains. However, the same reaction that removes stains also damages organic fibres, so today bleach is far more likely to be used as a toilet cleaner thanks to its antimicrobial properties.

Bleach is commonly a solution of a pale yellow-green chemical called sodium hypochlorite. This breaks down ‘chromophores’, the parts of some molecules that absorb certain wavelengths of light so that only some are reflected, giving colour. Until recently, little was known about sodium hypochlorite’s antimicrobial action, but it's now thought it causes a microbe’s proteins to unfold, destroying them.

Sodium hypochlorite decomposes slowly in water, releasing chlorine, which explains bleach’s characteristic smell. The reaction is slowed by the presence of an alkali, so bleach also usually contains a small amount of sodium hydroxide. Conversely, acid speeds up this reaction. For this reason, and because chlorine gas can cause serious lung damage, bleach should never be used in combination with other cleaning agents.

WASHING POWDER

THE WATER BOOSTER