This article is the characteristic of potassium in terms of physics and chemistry.The first of these sciences study the mechanical properties of materials and external.And the second - their interaction with each other - it's chemistry.Potassium - the nineteenth in a row element in the periodic table.It belongs to alkali metals.This article will be reviewed and the formula E, potassium and its behavior with other substances and t. D. It is one of the most active metals.The science that deals with the study of this and other elements - chemistry.Grade 8 includes the study of inorganic substances and their properties.Therefore, this article will be useful to students.So, let's begin.
Characteristics of potassium in terms of physics
This is a simple substance, which under normal conditions is in the solid state.The melting temperature of sixty-three degrees Celsius.It boils as the metal when the temperature reaches seven hundred sixty-one degrees Celsius.The subject matter has a silver-white color.It has a metallic luster.The density of potassium is eighty-six hundredths grams per cubic centimeter.It is a very light metal.The formula of potassium is very simple - it does not form molecules.This material consists of atoms which are arranged close together and have a crystalline lattice.The atomic mass of potassium equal to thirty-nine grams per mole.The hardness of its very low - it can be easily cut with a knife, like cheese.
Potassium and chemistry
begin with, that the potassium - a chemical element that has a very high chemical activity.Even store it in the open air is impossible, as it immediately begins to react with the surrounding substances.Potassium - a chemical element that belongs to the first group and the fourth period of the periodic table.It has all the properties that are characteristic of metals.
Interaction with simple substances
These include oxygen, nitrogen, sulfur, phosphorus, halogens (iodine, fluorine, chlorine, bromine).In order to consider the interaction of potassium each.Interaction with oxygen is called oxidation.During this chemical reaction consumes oxygenation and potassium in a molar ratio of four parts to one, resulting in the formation of the metal oxide in an amount of two parts.This reaction can be expressed by the following equation: 4K + O2 = 2K2O.In the combustion of potassium can be seen bright violet flame.Therefore, this reaction is considered to determine the quality of potassium.Reactions with halogens referred to in accordance with the chemical names of these elements, it iodination, fluorination, chlorination, bromination.These interactions can be called addition reactions, since atoms of the two different materials are combined into one.An example of this process is the reaction between potassium and chlorine, resulting in the formation of the metal chloride.To accomplish this interaction is necessary to take these two components - two moles of the first and one second.The result is two moles of the potassium compound.This reaction is expressed in this equation: 2k + = SІ2 2KSІ.With nitrogen potassium compounds can give during combustion in the open air.During this reaction consumes the metals and nitrogen in a molar ratio of one to six parts, as a result of the interaction of potassium nitride is formed in an amount of two parts.This can be shown by the following equation: N2 + 6K = 2K3N.This compound is green crystals black.With the metals react with phosphorus on the same principle.If you take three moles per mole of potassium and phosphorus, we obtain one mole phosphide.This chemical reaction can be written in the form of the reaction equation: 3K + p = K3R.In addition, potassium able to react with hydrogen forming a hydride.As an example can be given such an equation: 2K + H2 = 2 kN.All addition reactions occur only in the presence of high temperatures.
interaction with complex substances
Characteristics of potassium in terms of chemistry and provides consideration of the topic.By challenging substances which can react with potassium are water, acids, salts, oxides.With all of them the metals react differently.
Potassium and water
This chemical element reacts violently with it.This forms a hydroxide and hydrogen.If we take two moles of potassium and water, then we get the same amount of potassium hydroxide per mole of hydrogen.This chemical reaction can be expressed by the following equation: 2k + 2H2O = 2KOH = H2.
reactions with acids
Since potassium - active metal, it is easy to displace atoms of Hydrogen from their compounds.An example may be the reaction which takes place between the substance under examination and hydrochloric acid.For its implementation must take two moles of potassium, and the acid in the same amount.The result is a potassium chloride - two moles of hydrogen and - one mol.This process can be written in this equation: 2k + 2NSІ 2KSІ = + H2.
and potassium oxides
with this group of inorganic compounds of the metal reacts only with significant heating.If a metal atom constituting the oxide, passive addition, we are talking about in this article, there is, in fact, the exchange reaction.For example, if we take two moles of potassium oxide per mole of Cuprum, as a result of their interactions can be obtained from one mole of an oxide of a chemical element and considered pure cuprum.This can be shown in the form of this equation: 2K + CuO = K2O + Cu.That's where the exhibits strong reducing properties of potassium.
reacted with a base
Potassium is able to react with the metal hydroxides, which are located to the right of it in the electrochemical activity row.In this case also demonstrates its restorative properties.For example, if we take two moles of potassium per mole of barium hydroxide, the reaction of substitution we get substances such as potassium hydroxide in an amount of two moles and pure barium (mole) - it precipitates.Represented by the chemical interaction can be displayed as the following equation: 2K + Ba (OH) 2 = 2KOH + Ba.
reactions with salts
In this case, potassium still shows its properties as a strong reducing agent.Substituted by chemically more passive elements, it provides a pure metal.For example, when added to aluminum chloride in an amount of two moles of three moles of potassium, as a result of this reaction obtain three moles of potassium chloride and two moles of aluminum.To express this process with the help of the equation as follows: + 3K = 3KSІ2 2AІSІ3 + 2AІ.
reactions with fat
If you add potassium to any organic substance of this group, it also will replace one of the atoms of Hydrogen.For example, when mixed with stearin is formed of the metal stearate, potassium and hydrogen.This material is used for the manufacture of liquid soap.This characteristic of potassium and its interactions with other substances ends.
use of potassium and its compounds
Like all metals of concern in this article is essential for many processes in the industry.The main application of potassium occurs in the chemical industry.Due to its high reactivity, alkali metal and a pronounced reduction properties, it is used as a reagent for many interactions and the production of various substances.In addition, alloys with a content of potassium are used as coolants in nuclear reactors.Also considered in this article, the metal finds its application in electrical engineering.In addition to all of the above, it is one of the main nutrient for plants.Moreover, its compounds are used in various industries.Thus, in the extraction of gold potassium cyanide is used, which serves as a reagent for the recovery of value metals from ores.In the manufacture of glass used potassium carbonate.Phosphates are considered chemical element are components of various cleaning products and powders.In matches there this metal chlorate.In the manufacture of films for old cameras used bromide of the element.As you already know, it is possible to get by bromination of potassium at high temperatures.In medicine it is used chloride of the chemical element.In the soap - stearate and other derivatives of fat.
Preparation of the metal
Nowadays potash mined in the laboratory in two main ways.Origin - recovery of its by sodium hydroxide, which is more chemically active than potassium.And the second - getting it from chloride, with sodium, too.If added to one mole of potassium hydroxide as the sodium is formed on one mole of sodium hydroxide and pure potassium.The equation of the reaction is as follows: KOH + Na = NaOH + C. For the reaction to mix the second type of the metal chloride and sodium in equal molar proportions.This produces substances such as table salt and potassium in the same ratio.To express this chemical interaction is possible by means of the reaction equation: KSІ + Na = NaCl + K
structure
potassium atom of the chemical element, like all the others, consists of a nucleus, which contains protons and neutrons, and electrons,which rotate around it.The number of electrons is always equal to the number of protons that are inside the nucleus.If any electron disconnected or joined to the atom, it ceases to be neutral, and is converted into an ion.They are of two types: cations and anions.First have a positive charge, and the second - no.If joined to the atom of the electron, it is converted into an anion, and if any of the electrons leave its orbit, neutral atom becomes cation.Since the serial number of potassium, according to the periodic table, nineteen, and the protons in the nucleus of a chemical element is the same.Therefore, we can conclude that the electrons around the nucleus is located nineteen.The number of protons contained in the atomic structure can be determined by subtracting from the atomic mass of the sequence number of the chemical element.So we can conclude that the core is potassium twenty protons.As viewed in this article the metal belongs to the fourth period, it has four orbits, which are uniformly distributed electrons, which are always in motion.Driving potassium is as follows: in the first two electrons orbit located on the second - eight;as well as the third, the last, the fourth, the orbit rotates only one electron.This explains the high level of chemical activity of metal - its last orbit is not completely filled, so it tends to connect with any other atoms, causing their electrons past the orbits become common.
Where can I find this element in nature?
Since he has extremely high chemical activity on the planet, he never found in its pure form.He can be seen only as part of a variety of compounds.Mass fraction of potassium in the Earth's crust is 2.4 percent.The most common minerals, which include potassium - is Salvini and carnallite.The former has the following chemical formula: • NaCl KCl.It has variegated colors and is composed of a plurality of crystals of various colors.Depending on the ratio of potassium chloride and sodium, as well as the presence of impurities, it may contain red, blue, pink, orange components.The second mineral - carnallite - looks like a transparent, pale blue, pale pink or pale yellow crystals.Its chemical formula is as follows: KCl • MgCl2 • 6H2O.It is a crystalline hydrate.
role of potassium in the body, symptoms of deficiency and excess
He, along with sodium to maintain water and electrolyte balance of the cell.Also involved in the transmission between the membranes of the nerve impulse.In addition, it regulates the acid-base balance in the cell and the whole body in general.He is involved in metabolic processes, prevents the appearance of edema, is a part of the cytoplasm - about fifty percent of it - the salt of the metal.The main signs that the body lacks potassium is swelling, the occurrence of such diseases as edema, irritability and disorders in the nervous system, inhibition of reaction and memory impairment.In addition, the insufficient number of trace element adversely affects the cardiovascular and muscular systems.Lack of potassium for a very long time can cause a heart attack or stroke.But due to an excess of potassium in the body can develop ulcers of the small intestine.For the balance of the food so as to receive a normal amount of potassium, it is necessary to know in what products it contains.
Food with a high content of trace elements under consideration
First of all, it's nuts, such as cashews, walnuts, hazelnuts, peanuts, almonds.Also, a large amount is in the potatoes.In addition, the potassium found in dried fruits, such as raisins, apricots, prunes.Rich in this element, and pine nuts.Also, the high concentration observed in legumes: beans, peas, lentils.Seaweed is also rich in the chemical element data.Still other products containing active element in large quantities, are green tea and cocoa.Furthermore, in a high concentration and it is in many fruits, such as avocados, bananas, peaches, oranges, grapefruits, apples.Many cereals are rich in trace element under consideration.This is primarily barley and wheat and buckwheat.In parsley and brussels sprouts also have a lot of potassium.Furthermore, it is contained in carrots and melon.Onions and garlic have a considerable number of the chemical element considered.Eggs, milk and cheese also have a high content of potassium.The daily rate of this chemical element for the average person is three to five grams.
Conclusion After reading this article, it can be concluded that potassium is extremely important chemical elements.It is required to synthesize many compounds in the chemical industry.Also used in many other industries.Also it is very important for the human body, therefore, must regularly and in the required amount to do with food.
