13 Sep 2019

Potassium - a matter of life and death

From Elemental, 8:00 am on 13 September 2019

Potassium is a fundamental building block of life that pops up all over the place.

The name comes from the English word potash, an old term for potassium salts obtained from wood ash. The chemical symbol K comes from kalium, an Arabic term for alkaline – or al-kali- plant ashes. Germanic countries went with the common name kalium for element 19 for many years.

Potassium was discovered by the prolific element discoverer Humphrey Davy in 1807, who found it to be highly reactive with water. It also added a lovely violet colour to a flame, the same colour that is seen in the familiar potassium permanganate or Condy’s crystals.

Along with sodium, potassium is a critical part of the sodium-potassium pump, which is crucial for the transmission of nerve signals.

Bananas are a good dietary source of potassium, which is an essential element.

Industrially, most potassium is used in fertilisers as well as in soaps and detergents.

No caption

Photo: RNZ

You can subscribe to the Elemental podcast for free, at Apple Podcasts, Spotify, Stitcher, Google Podcasts, RadioPublic and iHeartRADIO.

The Elemental podcast is celebrating 150 years since the periodic table was first published by Russian chemist Dmitri Mendeleev.

Find out more about events during the United Nation’s International Year of the Periodic Table.

Professor Allan Blackman is at Auckland University of Technology.