• WordNet 3.6
    • n potassium a light soft silver-white metallic element of the alkali metal group; oxidizes rapidly in air and reacts violently with water; is abundant in nature in combined forms occurring in sea water and in carnallite and kainite and sylvite
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Webster's Revised Unabridged Dictionary
  • Interesting fact: Pumpkins contain potassium and vitamin A
    • n Potassium (Chem) An Alkali element, occurring abundantly but always combined, as in the chloride, sulphate, carbonate, or silicate, in the minerals sylvite, kainite, orthoclase, muscovite, etc. Atomic weight 39.0. Symbol K (Kalium).☞ It is reduced from the carbonate as a soft white metal, lighter than water, which oxidizes with the greatest readiness, and, to be preserved, must be kept under liquid hydrocarbons, as naphtha or kerosene. Its compounds are very important, being used in glass making, soap making, in fertilizers, and in many drugs and chemicals.
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Century Dictionary and Cyclopedia
  • Interesting fact: The average human body contains enough: iron to make a 3 inch nail,sulfur to kill all fleas on an average dog, carbon to make 900 pencils, potassium to fire a toy cannon, fat to make 7 bars of soap, phosphorous to make 2,200 match heads, and water to fill a ten-gallon tank.
    • n potassium Chemical symbol, K (for kalium); atomic weight, 39.1. The metallic base of the alkali potash, a substance not occurring uncombined in nature, but in various combinations widely diffused and of the highest importance. See potash. Potassium is silvery-white, and has a decided metallic luster. Its specific gravity is 0.875, and it is the lightest of all the metals with the exception of lithium. At the freezing-point of water it is brittle and has a crystalline fracture; at the ordinary temperature it is soft and may easily be cut with the knife. It was first obtained by Davy, in 1807, by the electrolysis of potash; but its preparation in the large way is effected by the ignition of a mixture of charcoal and potassium carbonate in a mercury bottle or iron tube coated with clay. In perfectly pure and dry air it undergoes no change; but in ordinary air it soon becomes coated with a film of potassium hydrate and carbonate. Its affinity for water is so great that when brought into contact with it immediate decomposition is effected, and sufficient heat evolved to set on fire the liberated hydrogen, which burns with the characteristic violet flame of potassium. Next to cæsium and rubidium it is the most electropositive element. It is a most powerful reducing agent, and hence has been largely employed for separating other metals from their various combinations; but at the present time sodium, being cheaper, is more generally employed for that purpose. Among the most important salts of potassium are the chlorid or muriate, KCI, mined at Stassfurt, Germany, and used as a fertilizer as well as the starting-point for the manufacture of other potash-salts; potassium chlorate, KClO3, which is used in the arts as an oxidizing agent and in the manufacture of explosives; potassium nitrate, KNO3, niter or saltpeter, made at present by the double decomposition of sodium nitrate and potassium chlorid, which is used in medicine and pyrotechny, but chiefly in the manufacture of gunpowder; potassium carbonate, K2CO3, which, under the commercial names of potash and pearlash, is largely used in the manufacture of soap and glass, and as a basis for making other potash-salts; potassium cyanide, KCN, a violent poison, used in photography and as a reducing agent; and potassium bichromate, K2Cr2C7, red chromate of potash, much used in dyeing and calico-printing.
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Chambers's Twentieth Century Dictionary
  • Interesting fact: The first US Patent was for manufacturing potassium carbonate (used in glass and gunpowder). It was issued to Samuel Hopkins on July 31, 1970.
    • n Potassium pō-tas′i-um the metallic base of the alkali potash—it is of a bluish colour, and presents a strong metallic lustre.
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Webster's Revised Unabridged Dictionary
NL. See Potassa Potash
Chambers's Twentieth Century Dictionary


In literature:

You need a good night's sleep and bromide of potassium.
"A Man's Woman" by Frank Norris
Sulphide of potassium, one ounce to a gallon of water, is also a reliable remedy.
"The Culture of Vegetables and Flowers From Seeds and Roots, 16th Edition" by Sutton and Sons
Thus, while potassium melts at 62.5 deg.
"Scientific American Supplement, No. 508, September 26, 1885" by Various
There is no black sticky mass of potassium salts left to foul the gun barrel.
"Creative Chemistry" by Edwin E. Slosson
With iodide of potassium Bright scarlet colour.
"Aids to Forensic Medicine and Toxicology" by W. G. Aitchison Robertson
C., the solubility being slightly increased by the presence of potassium bromide.
"Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3" by Various
Get a piece of lead pipe and use it as a funnel to introduce about 1-1/2 ounces of sulphite of potassium into any outside holes tenanted by rats.
"The Handy Cyclopedia of Things Worth Knowing" by Joseph Triemens
Also administer the following: Bromide of Potassium, twelve ounces; Nitrate of Potash, four ounces; Iodide of Potash, three ounces.
"The Veterinarian" by Chas. J. Korinek
Potassium sulphate, freezing point 1,958 deg.F.
"The Working of Steel" by Fred H. Colvin
Ferdinand had a Hunch that somebody was getting ready to drop Cyanide of Potassium into his Cup of Joy.
"Ade's Fables" by George Ade

In news:

Altered rumen fermentation, a key cause of milkfat depression, could be alleviated with potassium supplementation in the diet.
Potassium, the rumen , and milkfat depression.
Yellow potatoes contain 810 mg of potassium.
Their potassium content is higher than broccoli, bananas, and tomatoes.
Avocados contain 60 precent more potassium per ounce than bananas.
Bayer's Yaz product contains drospirenone, known to increase potassium levels in the blood.
Learn how this important mineral helps keep blood pressure in check—and how to eat more potassium rich foods.
Potassium deficiency symptoms are developing in corn and soybean crops in many parts of the state according to University of Illinois assistant professor of crop sciences Fabian Fernandez.
Potassium iodide not always handy after a meltdown.
Potassium (K) deficiency symptoms are developing in corn and soybean crops in many parts of the state, according to University of Illinois Assistant Professor of Crop Sciences Fabian Fernandez.
The research found that the people who are most at risk are those who get too much salt but also get too little potassium .
Randomized clinical trials have shown that increasing potassium intake can lower blood pressure.
Posts With Keyword ' Potassium Deficiency.
Potassium , Other Minerals Shown to Reduce Blood Pressure.
Potassium Sorbate - retards fermentation.

In science:

We therefore fit the amplitude of a potassium line model to the pixel-by-pixel data, with the model used in Huitson et al. (2012) to fit the potassium line and surrounding Rayleigh scattering slope, which is based upon the analytic expression from Lecavelier Des Etangs et al. (2008).
The prevalence of dust on the exoplanet HD 189733b from Hubble and Spitzer observations
As with the sodium feature, for the potassium cross-section we neglected pressure broadening due to the observed lack of broad line wings.
The prevalence of dust on the exoplanet HD 189733b from Hubble and Spitzer observations
The potassium feature in the ACS data is 2.5-σ significant.
The prevalence of dust on the exoplanet HD 189733b from Hubble and Spitzer observations
The model temperature scales to fit the amplitude of the potassium feature, with a best-fit value of 1800±720 K.
The prevalence of dust on the exoplanet HD 189733b from Hubble and Spitzer observations
Thus, while the lack of high-resolution data around the potassium line prevents very specific constraints, the bestfit solution is compatible with the presence of the line to the same level as the sodium line or higher, i.e. with a significant core but no broad wings.
The prevalence of dust on the exoplanet HD 189733b from Hubble and Spitzer observations