What is Metallic Character
The metallic character is a property that is unique to metals. It indicates the reactivity of a metal atom. Due to their low ionization energies, metals tend to lose electrons. Therefore, the metallic character is the ability of an atom to lose electrons and form a positively charged ion or cation. It is responsible for metallic properties like ductility, brittleness, malleability, luster, and electrical and thermal conductivities [1-4].
The opposite of the metallic character is the non-metallic character. It is generally associated with a nonmetal. It is defined as the ability of an atom to accept electrons and form a negatively charged ion or cation.
Metallic Character Periodic Trend
The metallic character displays a periodic trend among the periodic table elements. The metallic character is dependent on several essential atomic properties, such as atomic size, electron affinity, and ionization energy. Elements with low ionization energies display high metallic character [2-5].
Horizontal Trend: Metallic Character Across a Period
The metallic character decreases from left to right across a period in the periodic table. As the number of protons increases, the attractive electrostatic force between the nucleus and electrons increases, and the electrons are held tightly. Hence, it is not easy for atoms to give away electrons. The atoms towards the right of the periodic table prefer to accept electrons.
Vertical Trend: Metallic Character Down a Group
Down a group, the atomic number and the atomic radius increase. The inner electrons shield the outer electrons from the nucleus. As a result, the attractive forces between the protons and electrons decrease, making it easier for the atoms to give away electrons. Thus, the metallic character increases from top to bottom down a group in the periodic table.
A way to remember the horizontal and vertical trend is that the metallic character increases starting from the right of a period and going left. Down a group from top to bottom, the metallic character increases. Therefore, the metallic character increases diagonally from the top right to the bottom left, as shown in the image above.
The non-metallic trend is opposite to that of the metallic trend. Moving right across a period increases the non-metallic character. Up a group from bottom to top, the non-metallic character increases. Therefore, the non-metallic character increases diagonally from the bottom left to the top right, as shown in the image above.
From the above trend, it can be concluded that the alkali metals and alkaline-earth metals, except hydrogen, have the highest metallic character. On the other hand, nonmetals and halogens have the highest nonmetallic character.
Ans. Fluorine has the least metallic character. In other words, it has the most non-metallic character.
Ans. The element with the greatest metallic character is Francium.