Descale a kettle

Ten minutes, one ingredient, no scrubbing. The white crust is a mineral, so it needs an acid, not effort.

Warning

Limescale is calcium carbonate left behind as water boils away. Scrubbing polishes it; acid dissolves it. That is the whole job.

Step 1 of 4
Empty the kettle and fill it to about halfway with equal parts water and cleaning vinegar — or two tablespoons of citric acid in half a litre of water, which does the same thing without the smell.
Step 2 of 4
Bring it to the boil and switch it off.
Step 3 of 4
Wait 20 minutes
Leave it to stand. The scale loosens by itself; this is the part that replaces the scrubbing.
Step 4 of 4
Pour it away and look inside. Heavy scale may need a second round rather than a scourer.
Caution
Rinse and boil at least twice with clean water before making tea, and pour those boils away.
Descaling monthly in a hard-water area takes ten minutes. Leaving it for a year takes three rounds and still looks patchy.