The alkaline earth metals are a family of chemical elements that make up the second group of the modern periodic table. The members of the alkaline earth metal family include radium (denoted by the symbol ‘Ra’), barium (denoted by the symbol ‘Ba’), strontium (denoted by the symbol ‘Sr’), calcium (denoted by the symbol ‘Ca’), magnesium (denoted by the symbol ‘Mg’), and beryllium (denoted by the symbol ‘Be’). These elements are usually silvery-white and have a lustrous appearance. Furthermore, all alkaline earth metals are known to be fairly reactive under standard conditions of temperature and pressure (often abbreviated to STP). Almost all alkaline earth metals are known to occur naturally, with exception of radium (which is not a primordial element). However, radium is known to occur through the radioactive decay chains of thorium and uranium. Some important properties and applications of the alkaline earth metals are provided in this article.
Beryllium (Be)
Beryllium is a white-grey coloured metallic element whose atomic number is 4. The standard atomic weight associated with beryllium is approximately equal to 9.012 atomic mass units. This element corresponds to group 2 and period 2 of the modern periodic table. It is, therefore, an s-block element. The electronic configuration of beryllium can be written as [He]2s2. Under standard conditions for temperature and pressure, this element is known to exist in the solid phase. Owing to its stiffness, relatively low weight, and its dimensional stability over a wide temperature range, beryllium is known to be used for lightweight structural components in the aerospace and defence industries.
Magnesium (Mg)
Magnesium is a lustrous element that exists in the solid state under standard conditions for temperature and pressure. The atomic number of magnesium is 12. It belongs to group 2 and period 3 of the modern periodic table. The standard atomic weight of magnesium is approximately equal to 24.304 atomic mass units. This element can be classified as an s-block element. The electronic configuration of magnesium can be written as [Ne]3s2. Magnesium is known to be the 3rd most commonly used structural metal, after iron and aluminium. It is also used in super-strong lightweight alloys and materials.
Calcium (Ca)
Calcium is the chemical element which is denoted by the symbol ‘Ca’. The atomic number of calcium is 20. The standard atomic weight of this element can be approximated to 40.07 atomic mass units. Calcium belongs to group 2 and period 4 of the modern periodic table and can, therefore, be classified as an s-block element. The electronic configuration of this element can be written as [Ar]4s2. Under standard conditions for temperature and pressure, this element is known to exist in the solid state. Owing to its strong affinity for sulfur and oxygen, the primary use of this element is in steelmaking. It is also known to be used in maintenance-free automotive batteries.
The elements strontium, barium, and radium are also s-block elements. Their atomic numbers are 38, 56, and 88 respectively. Strontium is used in cathode ray tubes, barium is often alloyed with nickel for spark plugs, and radium is known to be used in the treatment of cancer.
