Potassium

Introduction

The element of potassium was first discovered by a well-known British chemist named Sir Humphry Davy in the year, 1807. The element was first, separated through the process of electrolysis from the compound named caustic potash or (KOH) that was in the molten state. However, potassium was collated in the cathode present within the system of electrolysis.

Figure 1: Potassium: Chemical element characteristics and uses

Potassium and Its Occurrences

The element of potassium is considered as the second lightest element, in simple words, potassium has the least density that is placed just after the element lithium. Potassium is denoted by the symbol K where, it is derived from the word Kalium. This chemical element can be categorised under the metals that are alkali in nature. It is noticed that potassium remains solid at room temperature or normal temperature.

Potassium is a soft metal that appears silvery white and its isotopes are widely available on the planet earth. The occurrences of potassium are predominantly found in the rocks of igneous, shale, as well as in various mineral sediments that include, orthoclase feldspar and muscovite. However, it is quite difficult to collect potassium elements as the elements that are associated with potassium are completely insoluble in water.

The compounds of potassium that are soluble in water involve, carnallite or $\mathrm{(KMgCl_3.6H_2O)}$, langbeinite or $\mathrm{(K_2Mg_2 [SO_4]_3)}$, polyhalite or $\mathrm{(K_2Ca_2Mg [SO_4]_4.2H_2O)}$ as well as sylvite or KCl. However, these elements are found underneath the river bed and also the sea beds that are ancient. The elements are electrolysed and are used for commercial purposes.

Potassium As a Metal

The metal potassium is considered as one of the most abundant elements found on earth and it is stated as the seventh. From the records, it is noticed that about 2.4% of the earth’s crust is made out of this element.

Figure 2: Potassium displayed in the Periodic table

The deposits of potassium are found in the compound form that is known as potassium chlorides that amounts to over a billion tonnes. This element is indelible in the lives of both animals and plants. This element has the atomic number that is 19 and has an atomic mass that is 39.0983 amu or atomic mass units.

Isotopes

The element potassium has three significant isotopes that include, 39,40 and 41. Of these, potassium-40 is stated to be highly reactive and is found in rocks, animals as well as plants.

The isotopes are primarily used in measuring the ages of objects. However, the isotopes tend to break down when there lay isotopes of argon.

Physical and Chemical Properties

The element of potassium has melting and boiling points that are 63o C and 770°C. As its physical properties, potassium floats in water and the element when segregated forms malleable in nature and appears as a silvery element. As chemical characteristics, potassium tends to react vigorously with water giving hydrogen thereby it can easily catch fire and explode. This element easily reacts with phosphorus, chlorine, sulphur, nitrogen and has a vapour that is green as well as a flame that is lavender in colour.

Reactions

Potassium violently reacts with water, thereby, giving out hydrogen gas and it is quite rapid in nature. The reaction is expressed as

$\mathrm{“2K(s) + 2H_2O\:\rightarrow\:2KOH (aq) + H_2 (g)”.}$

In presence, of air potassium turns into a tarnish colour and the reaction is displayed as

$\mathrm{“K(s) + O_2(g)\:\rightarrow\:KO_2(s)”.}$

Potassium: Application and General Facts

Varied applications are noted for potassium that involves, potassium chloride used as injections, in making soaps and detergents potash is used. More to this, potassium is used as a heat exchanger in nuclear power plants and salts of potassium are used in fertilizers.

The crucial fact in the process of electrolysis is that potassium was the first metal to be segregated. This is because prior to this incident it was quite difficult to make a differentiation among the elements of sodium and potassium. Prior to recognition, potassium was already in use for the production of soaps by mixing it with animal fat and as well as potassium carbonate.

Conclusion

In this tutorial, intensive focus has been given in order to understand the element named potassium. It is noticed that potassium is one of the most abundant elements found on earth and covers the earth’s crust about 2.4%. However, it is found in combined form and is isolated with the help of the process called electrolysis.

(FAQs)

Q1. Why the element of potassium is essential in the field of chemistry?

Ans. The element of potassium is essential in the field of chemistry, as it plays a crucial role in as it conducts proper functioning of the living cells. This is also used in the functioning of nerves and maintains the entire fluid system within the human body.

Q2. What are the five most crucial industrial usages of potassium?

Ans. The metal, potassium is beneficial to industrial usage for its wide applications. Potassium is used in the making of soaps as well as detergents that are used for sanitary purposes. In the mining of gold, potassium is used, and it is used in the production of glasses and dyes. More to this, it is used in the making of batteries and gunpowder.

Q3. What is the other name for the element potassium?

Ans. The other name for the element potassium, is potash that is taken from an English word, however, its chemical symbol is taken from the word, Kalium. The word, Kalium is Medieval Latinword forpotash which came from the Arabic word, qali that means, alkali.