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Potassium K
Where is potassium used--or where does it impact our everyday lives?
Potassium is a very reactive metal so does not occur uncombined in nature.
Potassium is a dietary necessity.
Name of element: Potassium symbol: K
Atomic number: 19 Atomic Mass: 39.10
Position on the periodic table: Group number (alkali metal): 1 Period 4
Melting point 65.5 oC (149.9 oF)
Boiling point 759 oC ( 1398.2 oF)
Reaction with air (oxygen): Potassium rapidly oxidizes in air. 4K + O2 --> 2K2O
Reaction with water: Rapid reaction, K catches fire 2K + 2H2O --> 2KOH + H2
Electron configuration: 2,8, 8, 1
Source: LANL.gov
Researcher: Frances M.
Many minerals are chlorides. These are sylvite, KCl, samples from IMC Fertilizer Carlsbad mine. Carlsbad, Mexico on display at the National Museum of Natural History in Washington D.C. viewed during a Chemistry One field trip.
WIS Photographer
Below--a bottle with fragments of elemental potassium-stored under oil to keep air away from the reactive metal.
Phlogopite, KMg3(Si3Al)O10(F,OH)2 also known as magnesium mica, on display at the National Museum of Natural History in Washington D.C. viewed during a Chemistry One field trip. It includes element number 19 on the periodic table: potassium, a soft silvery white metal with a density of 0.862 g/cm3. Potassium can be found in Canada and makes about 1.5% of the Earth’s crust.
Granite
From Conway, New Hampshire, USA displayed in the National Museum of Natural History, Washington DC and viewed during a Chemistry One field trip contains over 4% potassium oxide, K2O
Photographer: Annarosa Z
Microcline with albite viewed in the National Museum of Natural History, Washington DC
Formula: KAlSi3O8
Where found: Keyhole vug, Crystal Park, Florissant, Colorado, USA containing potassium
Photographer: Annarosa Z
Potassium is found in bananas. The FDA notes that a medium-sized banana (~126 g {4.5 %} contains 450 mcg potassium, which is 13 % of the recommended daily allowance.
Here Jair A is preparing banana skins to make a banana plastic as part of his Grade 10 project.
Below: samples of the banana plastic
Another sample of sylvite, KCl, from Stassfurt, Stachen, Germany
A freshly cut piece of potassium. Potassium is a soft metal and can easily be cut with a spatula. It is a very reactive metal and stored under oil to stop reactions with air. The sample to the left has some corrosion on the outside.
See the video of the cutting of the piece of potassium. The fragment is ~1 cm (0.4 in) wide.
WIS Photographer
