Atomic Number Of Potassium

Posted on  by admin

So if you look for potassium (symbol K in the periodic table), you will find that it has the atomic number of 19. This tells you that potassium has 19 protons and - since the number of protons is the same as the number of electrons- also 19 electrons. To find out the number of neutrons you have to look at the atomic mass or weight of the element.

  1. Atomic Number Of Potassium Atom
  1. A neutral atom of calcium, atomic number 20, contains 20 protons and 20 electrons. It has zero net charge. We calculate the number of neutrons in an atom from its mass number and atomic number: Potassium has a mass number of 39 and an atomic number of 19. Click to see full answer.
  2. Potassium (K) is a silver-white coloured metal that has the atomic number 19 in the periodic table. It is an Alkali Metal and is located in Group 1 of the periodic table. It has the symbol K.

Chemical properties of potassium - Health effects of potassium - Environmental effects of potassium

Atomic number


Atomic mass

39.0983 g.mol -1

Electronegativity according to Pauling



0.86 -3 at 0 °C

Melting point

63.2 °C

Boiling point

760 °C

Vanderwaals radius

0.235 nm

Ionic radius

0.133 (+1)



Electronic shell

[ Ar ] 4s1

Energy of first ionisation

418.6 kJ.mol -1

Discovered by

Sir Davy in 1808


The name is derived from the english word potash. The chemical symbol K comes from kalium, the Mediaeval Latin for potash, which may have derived from the arabic word qali, meaning alkali.
Potassium is a soft, silvery-white metal, member of the alkali group of the periodic chart. Potassium is silvery when first cut but it oxidizes rapidly in air and tarnishes within minutes, so it is generally stored under oil or grease. It is light enough to float into water with which it reacts instantly to release hydrogen, which burns with a lilac flame.

The chemistry of potassium is almost etirely that of the potassium ion, K+.


Most potassium (95 %) goes into fertilizers and the rest goes mainly into making potassium hydroxide (KOH), by the electrolysis of potassium chloride solution, and then converting this to potassium carbonate (K2CO3). Potassium carbonate goes into glass manufacture, expecially the glass used to make televisions, while potassium hydroxide is used to make liquid soaps and detergents. A little potassium chloride goes into pharmaceuticals, medical drips and saline injections.
Other potassium salts are used in baking, photography and tanning leather, and to make iodize salts. In all cases it is the negative anion, not the potassium, which is the key to their use.

Potassium in the environment

Most potassium occurs in the Earth's crust as minerals, such as feldspars and clays. Potassium is leached from these by weathering, which explains why there is quite a lot of this element in the sea (0.75 g/liter).
Minerals mined for their potassium are pinkish and sylvite, carnallite and alunite. The main mining area used to be Germany, which had a monopoly of potassium before the first World War. Today most potassium minerals come from Canada, USA and Chile. The world production of potassim ores is about 50 million tonnes, and reserves are vast (more than 10 billion tonnes).
Potassium is a key plant element. Although it is soluble in water, little is lost from undisturbed soils because as it is released from dead plants and animal excrements, it quickly become strongly bound to clay particles, and it is retained ready to be readsorbed by the roots of other plants.

Health effects of potassium

Potassium can be found in vegetables, fruit, potatoes, meat, bread, milk and nuts. It plays an important role in the physical fluid system of humans and it assists nerve functions. Potassium, as the ion K+, concnetrate inside cells, and 95% of the body's potassium is so located. When our kidneys are somehow malfunctioning an accumulation of potassium will consist. This can lead to disturbing heartbeats.

Potassium can effect you when breathed in. Inhalation of dust or mists can irritate the eyes, nose, throat, lungs with sneezing, coughing and sore throat. Higher exposures may cause a build up of fluid in the lungs, this can cause death. Skin and eye contact can cause severe burns leading to permanent damage.

Environmental effects of potassium

Together with nitrogen and phosphorous, potassium is one of the essential macrominerals for plant survival. Its presence is of great importance for soil health, plant growth and animal nutrition. Its primary function in the plant is its role in the maintenance of osmotic pressure and cell size, thereby influencing photosynthesis and energy production as well as stomatal opening and carbon dioxide supply, plant turgor and translocation of nutrients. As such, the element is required in relatively large proportions by the growing plant.

The consequences of low potassium levels are apparent in a variety of symptoms: restricted growth, reduced flowering, lower yields and lower quality produce.
High water soluble levels of potassium cause damage to germinating seedlings, inhibits the uptake of other minerals and reduces the quality of the crop.

Check out our potassium in water page

Back to the periodic table of elements

More from 'Elements'

Lenntech (European Head Office)

Distributieweg 3
2645 EG Delfgauw
The Netherlands
Phone: +31 152 610 900
fax: +31 152 616 289
e-mail: [email protected]

Lenntech USA LLC (Americas)

5975 Sunset Drive
South Miami, FL 33143
Phone: +1 877 453 8095
e-mail: [email protected]

Atomic Number Of Potassium
Lenntech DMCC (Middle East)
Atomic Number Of Potassium

Level 5 - OFFICE #8-One JLT Tower
Jumeirah Lake Towers
Dubai - U.A.E.
Phone: +971 4 429 5853
e-mail: [email protected]

Copyright © 1998-2021 Lenntech B.V. All rights reserved

What is the electron configuration, orbital diagram, and noble gas notation of potassium?

1 Answer

Potassium's atomic number is 19. This means that every atom of potassium has 19 protons in its nucleus. In a neutral atom, the number of protons is equal to the number of electrons. So the electron configuration of potassium will involve 19 electrons.

The full electron configuration of potassium is #'1s'^2'2s'^2'2p'^6'3s'^2'3p'^6'4s'^1'#.

The noble gas notation is #'[Ar]4s'^1'#.

The following orbital diagram shows the increase in energy from one energy sublevel to the next, but you can write them on the same level horizontally,

Atomic Number Of Potassium Atom

Related questions