An atom has protons and electrons. The protons are placed in the nucleus of the atom while the electrons are situated in the orbital shell of the atom. The way these electrons are positioned is known as the electron configuration1. Each shell can hold a certain amount of electrons before moving onto the next shell. In the electron configuration, four letters are used as subshells to indicate how many electrons the shell can hold before moving onto the next one in the orbital2. These subshells are s, p, d and f. The s-subshell block is the first two left-sided column and the six columns on the far right side of the table are known as the p-subshell block. The d-subshell block is the middle ten columns and the f-subshell block is the separated fourteen columns filled with the lanthanoids and the actinoids3. An electron configuration is displayed in this manner5:1s22s22p63s23p2 This is the electron configuration of the element, Silicon. The superscript, written as (x) in the configuration (e.g. 2s(x)) represents the number of electrons in the subshell.The first shell contains 2 electrons. The second shell is composed of the subshells “2s” and “2p”. The s-subshell can hold a maximum of 2 electrons while the p-subshell can hold a maximum of 6 electrons. Together, they form the second electron shell, which can hold a maximum of 8 electrons before moving onto the next shell. On the Periodic table, elements are grouped according to a number of different factors. Some of the factors are:The number of orbital shells that are around the atom. For example: the descending order of the sixth column (the noble gases) in the “p” block shows that Neon has two shells, Argon has three, Krypton has four shells4 and so forth… The increasing number of electrons in the shells. Going across the periodic table, we see that the atomic number increases. This number represents the number of electrons in the atom6 so therefore, Hydrogen is the first element in the periodic table because it has 1 electron and the last element, Oganesson has 118 electrons. The finishing subshell. For example: Lithium is found in the “s” block because its electron configuration ends with “3s1”. Sulphur is in the “p” block because its electron configuration ends with “3p4” etc. In conclusion, the electron configuration of the element shows how that atom may react with another atom in a different element. Its position in the periodic table helps to identify the similarities with other elements in that group too. Their groupings (s block, p block etc) reveals that the elements in that group may or may not readily react with another element within the same group or in a different group. It shows the similarities in those elements.7.