Potassium

Isotope	NH	t_1/2	ZM	CPU M eV	ZP
³⁸ K	{syn.}	7.636 min	ε	5.913	³⁸ acre
³⁹ K	93.26%	K 40 K 0.012% 1,277 are
^stable with	20	neutrons · 10⁹ A	β^- ε	1,311 1.505	⁴⁰ approx. ⁴⁰ acre
⁴¹ K	6.73%	K 42 K are stable {
^syn.	with 22 neutrons}	12.360 h	β^-	3.525	⁴² approx.
⁴³ K	{syn.}	22.3 h	β^-	1.815	⁴³ approx.

NMR characteristics

	³⁹ K	⁴¹K
nuclear spin	3/2	3/2
gamma/ wheel/T	1,248 · 10⁷	6,852 · 10⁶
sensitivity	0.000508	8,4 · 10^-5
Larmorfrequenz with B = 4.7 T	9.33 M cycles per second	of 5.12 M cycles per second

as far as possible and common, become SI-UNITs uses.
If not differently notes,
the indicated data apply with standard conditions.

Potassium, (from potash arab. aluminium qalja = plant ash) is a chemical element of the 1. Main group of the periodic system with the ordinal number 19.

1 history
2 Occurrence
3 characteristics
4 use
5 biological meaning
6 proof of potassium
7 connections
8 sources
9 Web on the left of

[work on]

history

to 19. November 1807 reported Davy,he succeeded in winning by electrolysis of weakly dampened corroding alkalis two different metals; it called the metal Sodium (this is this very day the French and English name for sodium), because it is contained in soda, thatother Potassium (= English and French name for potassium), because one can win it from potash. In the German language area the Sodium Davys is designated since 1811 after a suggestion of Berzelius as sodium, during one for the Potassium Davys thatof Klaproth 1796 imported expression potassium (of arab.: aluminium-qali = ash, from plant ash profitable) took over.

[Work on]

occurrence

potassium occurs in nature only as cation in potassium connections. In the sea water the average concentration lies with approximately 0.38 office⁺ /l.

Naturally occurring kaliumhaltige minerals are:

Sylvin - KCl
Sylvinit - KCl * NaCl
Carnallit - KCl * MgCl₂ * 6 H₂ O
dock rivet - KCl * MgSO₄ * 3 H₂ O
Schönit - K₂ SO₄ * MgSO₄ * 6 H₂ O
Polyhalit - K₂ SO₄ * MgSO₄ * MgSO₄ * 2 CaSO₄
Orthoklas (Kalifeldspat) - K [AlSi₃ O₈]
Muskovit (potash mica) - KAl₂(OH, F)₂ [AlSi₃ O₁₀]

[work on]

to characteristics

potassium

similar to the other alkali metals potassium reacts with other elements and connections very violently and occurs in the natural environment only in bound form. Chemically it is more reactiveas sodium. Potassium reacts violently with water under formation of potassium hydroxide and release of hydrogen. With Luftzutritt the hydrogen, it catches fire can thereby to Verpuffungen and explosions come. In dry oxygen it burns under violet flame too Potassium hyperoxide KO₂. At damp air it continues to react with water and carbon dioxide to potassium carbonate. In liquid ammonia potassium, like all alkali metals, is well soluble under education of a blue-violet solution. With the halogens bromine and iodine sit downPotassium under detonation to the appropriate halides over.

The disposal of potassium is done via careful bringing in of small pieces of the metal in a large surplus of third Butanol, in which it dissolves under formation of the alcoholate.

At air becomes encrustedthe silver-white shining plane of section of the fresh metal within seconds with a bluish resplendent oxide coating. Metallic potassium is therefore kept under inert gas or paraffin oil. Contrary to sodium potassium knows crusts from oxides, peroxides and hydroxides with longer storage neverthelessform, which can cover the metal in form of reddish-yellow layers and explode those with contact or pressure. A safe disposal is then no longer possible, here offers itself only the burn-up of the complete bundle under controlled conditions.

Potassiumin the nutrition

in g/kg and 87% T

Grass products 25-35g

potatoes 20g

Bierhefe 21g

wheys 22-25g

lactose molasses 35g

Sojaschrot 20g

field beans 11g

peas 10g

RWS cake 14g

bran 10-13g

[work on]

use

potassium becomes mainly in fast breeders in forma NAK alloy as coolant assigned. Otherwise metallic potassium has only small technical meaning, since it can be replaced by the cheaper sodium.

Doping from tungsten wires to the production of lamp spirals
NAK heat alloy (see sodium)
potassium air cleaner ( potash cartridges) among other things upSubmarines for air filtering in the employment

[work on]

biological meaning

[work on]

meaning as fertilizer

water-soluble potassium salts are used predominantly as fertilizers, since plants can unlock the Kaliumsilicate occurring in the soil badly.

Important kaliumhaltige fertilizers:

Grain potash with MgO
patent potash
Potassium sulfate
Flory
Nitrophoska
Hakaphos

[work on]

meaning for the body

potassium is an essential mineral material, the daily need of humans lies with approximately 2 G. Potassium realms food are among other things Mushrooms, bananas, beans, Chilies, cheese, spinach and potatoes, init with up to 5 g Kalium/100 g food seems to those.

In the body potassium plays an outstanding role with the regularization of the diaphragm potential. The intrazelluläre potassium concentration is with approximately 150 mmol/l, is extracellular to 4 mmol/l. The concentration on Sodium lies intrazellulär with approx. 10 mmol/l, extracellularly with 140 mmol/l. These concentration differences are received by the Na/K ATPase upright and are vital for the function of the cell. Durable shifting of these cellular concentrations can with more increased (Hyperkaliämie) ormore degraded (Hypokaliämie) arise to blood potassium concentration and leads to disease symptoms, which can be life-threatening. The poison syringe used in the USA to executions contains Kaliumchlorid, which leads to a paralysis of the heart musculature and thus to death. Potassium belongs to thatmost important electrolytes of the body fluid and is for the controlling of the muscle activity with responsible. With high speed sportsmen it can come by excessive Ausschwitzen from potassium to cramps and exhaustion conditions.

[Work on]

radioactivity

potassium consists to 0.012% of the radioactive isotope ⁴⁰K and causes nearly 10% for the natural radioactive load of a Federal citizen (0.17 mSv /a to 2.1 mSv/a <ref>Federal Office for radiation protection< /ref>.

[Work on]

one knows proof

of potassium apart from the spectroscopic proof in water loosened potassium - ionsprove with ion-selective electrodes. Most potassium electrodes use the specific integration of potassium by Valinomycin C₅₄ H₉₀ N₆ O₁₈, which are embedded in a concentration of approximately 0.7% into a plastic diaphragm.
In addition is thatqualitative potassium proof by means of perchloric acid mögich. It forms its Kaliumperchlorat, a white precipitation.
Potassium can quantitative be determined with the help of gravimetry. Here potassium weighed out as Tetraphenylborat pleases and the received precipitation.