You boil water in a pot and find that there is a white coating lining the inside of the pot after you are done. What happened?
A) The pot must have had a mineral in it already and water stirred it up.
B) The pot was dirty.
C) Water evaporated and left bacteria on the inside of the pot.
D) The mineral precipitated from the water as the water boiled off as steam.

Question

Quizplus · Accepted Answer

The white coating lining the inside of the pot is likely mineral deposits that precipitated out of the water as it boiled and turned into steam. This happens when the water contains high levels of dissolved minerals like calcium and magnesium. As the water boils, it releases steam, leaving behind these mineral deposits on the surface of the pot.

You Boil Water in a Pot and Find That There