Seven elements in column (group) 1 (alkali metals).
In the Periodic table, potassium is one of seven elements in column (group) 1 (alkali metals): they all have a single valence electron in their outer electron shell, which they readily give up to create an atom with a positive charge-a cation, and combine with anions to form salts. The English name for the element potassium comes from the word  potash , and refers to the method by which potassium was obtained – placing in a pot the ash of burnt wood or tree leaves, adding water, heating, and evaporating the solution. Potassium is a chemical element with symbol K (derived from Neo-Latin, kalium) and atomic number 19. It was first isolated from potash, the ashes of plants, from which its name is derived. The English name for the element potassium comes from the word  potash , and refers to the method by which potassium was obtained – placing in a pot the ash of burnt wood or tree leaves, adding water, heating, and evaporating the solution. Potassium is pronounced as poh-TASS-ee-em. History and Uses: Although potassium is the eighth most abundant element on earth and comprises about 2.1% of the earth's crust, it is a very reactive element and is never found free in nature. Potassium chloride (KCl) is the most common potassium compound. It is used in fertilizers, as a salt substitute and to produce other chemicals. Potassium hydroxide (KOH) is used to make soaps, detergents and drain cleaners. Potassium ions are necessary for the function of all living cells. Potassium ion shifts across nerve cell membranes are necessary for normal nerve transmission: potassium depletion or excess can result in numerous abnormalities, including an abnormal heart rhythm and various electrocardiographic (ECG) abnormalities. The English name for the element potassium comes from the word  potash , and refers to the method by which potassium was obtained – placing in a pot the ash of burnt wood or tree leaves, adding water, heating, and evaporating the solution. Having too much potassium in the blood is called hyperkalemia; having too little is known as hypokalemia. Keeping the right potassium balance in the body depends on the amount of sodium and magnesium in the blood. Too much sodium -- common in Western diets that use a lot of salt -- may increase the need for potassium. The most important use of potassium is to treat the symptoms of hypokalemia (low potassium), which include weakness, lack of energy, muscle cramps, stomach disturbances, an irregular heartbeat, and an abnormal EKG (electrocardiogram, a test that measures heart function). Pure potassium is a soft, waxy metal that can be easily cut with a knife. It reacts with oxygen to form potassium superoxide (KO 2) and with water to form potassium hydroxide (KOH), hydrogen gas and heat. Enough heat is produced to ignite the hydrogen gas. Potassium chloride (KCl) is the most common potassium compound. It is used in fertilizers, as a salt substitute and to produce other chemicals. Potassium hydroxide (KOH) is used to make soaps, detergents and drain cleaners. Potassium forms an alloy with sodium (NaK) that is used as a heat transfer medium in some types of nuclear reactors. Potassium forms many important compounds. Potassium chloride (KCl) is the most common potassium compound. It is used in fertilizers, as a salt substitute and to produce other chemicals. Potassium hydroxide (KOH) is used to make soaps, detergents and drain cleaners. Potassium metal is far too reactive to be found uncombined in nature. The element is quite abundant and makes up about 1.5 % by weight of the earth's crust. Potassium is found extensively as potash (KOH). It is mined in Germany, USA, and elsewhere. Minerals such as sylvite (KCl), carnallite, and langbeinite, are found in ancient lake and sea beds. Potassium is a very important mineral for the proper function of all cells, tissues, and organs in the human body. It is also an electrolyte, a substance that conducts electricity in the body, along with sodium, chloride, calcium, and magnesium. Potassium is crucial to heart function and plays a key role in skeletal and smooth muscle contraction, making it important for normal digestive and muscular function. The most important use of potassium is to treat the symptoms of hypokalemia (low potassium), which include weakness, lack of energy, muscle cramps, stomach disturbances, an irregular heartbeat, and an abnormal EKG (electrocardiogram, a test that measures heart function). The alkali metals are a group (column) in the periodic table consisting of the chemical elements lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). After 1869, Dmitri Mendeleev proposed his periodic table placing lithium at the top of a group with sodium, potassium, rubidium, caesium, and thallium. Two years later, Mendeleev revised his table, placing hydrogen in group 1 above lithium, and also moving thallium to the boron group.
https://en.wikipedia.org/wiki/Potassium https://en.wikipedia.org/wiki/Potassium http://education.jlab.org/itselemental/ele019.html https://en.wikipedia.org/wiki/Potassium http://umm.edu/health/medical/altmed/supplement/potassium http://education.jlab.org/itselemental/ele019.html http://education.jlab.org/itselemental/ele019.html http://www.webelements.com/potassium/ http://umm.edu/health/medical/altmed/supplement/potassium https://en.wikipedia.org/wiki/Group_1_element
what group is potassium in