The various varieties of elements are categorized into blocks in the periodic table. These blocks are characterized by the characteristic orbitals of the valence electrons. Each block contains a set of elements that share the same orbital for the d and f orbitals. The block concept was introduced by Charles Janet. It originated from his description of spectroscopic lines of atomic orbitals. He also noted that the same element in the same group would react in similar ways. These properties are justified by the distinctive nature of the elements. The periodic table contains four blocks. These are d, p, f, and s. The d block corresponds to transition metals. These elements are useful for high-temperature conductance. The f block contains actinides and lanthanides. The s block contains alkali metals. The p block contains metalloids and non-metals. The s block contains 14 elements. Hydrogen is the lightest element and has the atomic number of one. These elements include alkali metals, lithium, and boron. All of such materials have high thermal and electrical ductility. But they can’t be 100% authentic. They can be oxidized to form a cation with a negative charge. The p block contains metals, non-metals, and metalloids. These elements have all of the valence electrons in the p orbital. These elements are used in medicine. The p orbital is usually filled with one, two, or six electrons. They have stable oxidation states from -1 to +1. They form ionic bonds with metals (Jena, 2013).
Blocks of The Periodic Table of Elements
1. Elemental block
The table of elements is typically broken up into four sections. All these blocks are based on the electron configuration of elements. There are 118 known elements in the periodic table (Constable, 2019).
1.1. Location of s block
The s-block is located on the left side of the periodic table. The elements in the s-block are highly electropositive and have low ionization energies. The elements in the s-block can form both dipositive and mono-positive cations. The reactivity of the elements in the s-block increases as the size of the atom increases.
1.2. Location of d block
The d-block is located between the p-block and the s-block of the periodic table. These elements are also known as transition elements. Due to their ability to undergo oxidation and reduction, they play an important role as catalysts in a wide variety of chemical reactions. The d-block does not include all of fundamental components in its makeup. The d-block elements include lanthanum, yttrium, scandium, and actinium.
1.3. Location of p block
To the right of the main body of the periodical tables is where you’ll find the p-block. The elements in this block are mostly metalloids. The elements in this block include metals of groups 3 to 8 as well as nonmetals. These elements are commonly used in medicine.
1.4 Location of f block
The f block is located at the bottom of periodic table which include lanthanide and actinide.
2. Trend of the blocks of periodic table
Generally, the size of atoms increases as we move down the periodic table. The number of valence electrons is similar between elements of adjacent groups. Non-metallic elements decrease in character as they move down the table. This trend is most pronounced between the lightest member of one group and the element of the next group (Ruskoski & Boal, 2021).
2.1. First four elements
The first four elements are placed on the S block, which is a horizontal column on the Periodic Table. These elements have two valence electrons. The number of valence electrons for these elements is determined by the group number.
2.2. Next six elements
The next six elements are placed on the p block. The p block elements have one valence electron. These elements can form covalent compounds. It is not quite clear what each element in this class is like. They include post-transition metals. These elements include B, F, Si, and Li. These elements have electron affinities of -200.4 kJ/mol.
2.3. Next eight elements
The next eight elements are d-block elements. These elements are transition metals. Their properties are similar to those of s-block elements. They have (n-1) d-orbital. They also have the last electron in the penultimate shell. These elements also have a half filled subshell.
3. Elements organized by block
Organizing elements in a periodic table by block is a way of putting them into familiar groups. The average distribution of valence electrons among elements in the similar group is around the identical. During the early days of chemistry, scientists were able to make a rudimentary understanding of the periodic table. This understanding was gradually refined when new elements were discovered. Today, there are 118 elements that can be found in the modern periodic table. In addition, the modern table includes Nobel gas groups, as well as separate transition elements (Constable, 2019; Ruskoski & Boal, 2021).
3.1. Structured into block
The modern periodic table is structured into blocks, which are groups of elements with a common subshell. Each block is justified by its own unique nature. Each block contains elements that are similar in chemical properties. These elements often form ionic compounds with non-metals. For example, helium is a s-block element, but it is not included in the p-block. This is because helium can only display one stable oxidation state.
3.2. Main groups
There are two main groups of elements. These are the s-block and p-block. Both groups contain elements from groups 1 and 2. The s-block includes alkali metals and alkaline earth metals. The p-block contains metalloids, halogens, and noble gases. The s-block includes alkaline earth metals and hydrogen. It also includes elements that have one electron in the s-subshell. These include sodium, lithium, beryllium, and cesium. It is also made up of non-metals such as helium. The p-block contains elements that form covalent bonds with other elements by sharing their electrons. The elements of this block can have up to six valence electrons. These elements can be found on the left side of the periodic table. The elements in this block tend to be more electropositive and have low melting points.
Conclusion
Generally, there are four blocks in the periodic table. Each unit is made up by a collection of components that all have the same orbital. The orbital contains the valence electrons of the elements in the block. The position of an element within a block is also important.
References
Jena, P. (2013). Beyond the periodic table of elements: The role of superatoms. The Journal of Physical Chemistry Letters, 4(9), 1432-1442.
Constable, E. C. (2019). Evolution and understanding of the d-block elements in the periodic table. Dalton Transactions, 48(26), 9408-9421.
Ruskoski, T. B., & Boal, A. K. (2021). The periodic table of ribonucleotide reductases. Journal of Biological Chemistry, 297(4).