Alkaline earth metals are a group of six chemical elements in the periodic table. There are six elements in this group: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). At ordinary temperature and pressure, all of the elements have extremely similar properties: they are all lustrous, silvery-white, moderately reactive metals.
They (together with helium) share a full outer s-orbital structurally; this orbital contains both of its two electrons, which the alkaline earth metals rapidly lose in order to form cations with charge +2 and an oxidation state of +2.
All of the identified alkaline earth metals occur naturally, with the exception of radium, which occurs exclusively as a byproduct of the decay of uranium and thorium, rather than as a primordial element. There have been numerous unsuccessful attempts to synthesise element 120, the group’s next possible member.
Why are they referred to as Alkaline Earth Metals?
The old-fashioned names for the alkaline earths, beryllia, magnesia, lime, strontia, and baryta, after their oxides, are the inspiration for the alkaline earth metals. These oxides are easy to dissolve in water (alkaline).
Among the second group’s constituents are beryllium as well as the metals strontium, barium, and radium. These elements are known as Alkaline Earth metals for two reasons: their oxides survive in the earth’s crust and are extremely heat stable.
The elements in group 1 of the periodic table are alkali metals. Alkaline earth metals make up the second group of the periodic table. Alkali metals have one valence electron, whereas alkaline earth metals have two valence electrons. This is the primary difference between the two types of metals.
Any one of the six chemical elements in Group 2 (IIa) of the periodic table. For example, Be, Mg, Ca, Sr, Ba, and radium make up the group of elements (Ra).
The occurrence, properties, and applications
Nonmetallic, water-insoluble, and fire-unalterable substances were referred to as “earths” prior to the nineteenth century. It was the alkaline earths, such lime (calcium oxide), that looked like the alkalies (sodium ash and potashes). As a result, alkaline earths, such as alumina and the rare earths, were distinguished from other earths and from the alkalies. While previously thought to be elements by the early 1800s, it became obvious that the earths are actually composites of a metal and oxygen. Dmitry Mendeleyev, a Russian chemist, proposed his first periodic chart in 1869, and since then, the alkaline-earth metals have been placed in Group 2 (IIa) of the periodic table.
The atoms of alkaline-earth metals, like those of the Group 1 (Ia) alkali metals, readily lose electrons and transform into positive ions (cations). Consequently, ionic salts make up the vast majority of their characteristic compounds: metal cations M2+ in salts containing any Group 2 element. Unless they contain a coloured anion, the salts are colourless (negative ion). Alkali metals (which contain M+ ions), sodium chloride (NaCl), and sodium monoxide (Na2O) have chemical formulae that can be compared to those of common alkaline-earth compounds such as calcium chloride and calcium oxide (Na2O).
Alkaline-earth metal oxides have basic oxidations (i.e., alkaline, in contrast to acidic). From beryllium, the lightest member of the group, to radium, the heaviest, an increase in electropositive character is noticed. Thus, beryllium oxide is actually amphoteric rather than basic as a result of this development; on the other hand, barium oxide is strongly basic. As reducing agents, metals quickly give away electrons to other compounds that are reduced in the process of reducing the metal itself.
All metals and their compounds, with the exception of radium, have some commercial use, although magnesium alloys and a wide range of calcium compounds stand out. Magnesium and calcium, particularly the latter, are abundant in nature and play important roles in geological and biological processes. Rare and radioactive, radium is an important element. Despite the fact that its compounds were commonly used in the first part of the twentieth century for cancer treatment, they have since been substantially replaced by less expensive alternatives.
History
Lime (Latin calx), which is now known to be calcium oxide, was employed in the construction of mortar in ancient times. In 1755, a Scottish chemist named Joseph Black discovered that magnesia, the oxide of magnesium, was an alkaline earth distinct from lime in that it produced a soluble sulphate rather than an insoluble sulphate, as was previously known. Heavy spar, also known as barys (Greek for “heavy”), was discovered in 1774 by Carl Wilhelm Scheele, the Swede who discovered oxygen and who established the presence of a new earth, afterwards known as baryta (barium oxide). The London chemists William Cruickshank and Adair Crawford identified strontia (strontium oxide) in 1789 after investigating a mineral (strontium carbonate) found in a lead mine in Argyllshire, Scotland. Nicolas-Louis Vauquelin, a French analytical chemist, discovered that the mineral beryl contained beryllium oxide and identified it as an earth in 1798. Alumina (aluminium oxide) was initially mistaken for beryllia because both dissolve in alkali, but beryllia was demonstrated to be unique because, unlike alumina, it reprecipitated when the alkaline solution was heated for long time. Because of its sweetness, Beryllia was previously referred to as “glucina” (Greek glykys). (In France, beryllium is still referred to as glucinium by this etymological root.)
Conclusion
From the following article we can conclude that The alkali metals are so named because they react with water to generate alkalies, which is what gives them their name. Alkalies are compounds of these elements that are hydroxide in nature, such as sodium hydroxide and potassium hydroxide. Alkalies are extremely powerful bases that are also caustic in nature. Any of the six chemical elements that make up Group 2 (IIa) of the periodic table are classified as alkaline-earth metals. Beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra) are the elements in question (Ra).