Question

Why is the nomenclature for Mercury (I) Fluoride \[H{g_2}{F_2}\] and not \[HgF\] ?

Answer 1

Hint: Metals are the chemical elements that can easily undergo loss of electrons. Non-metals are the elements that can attract electrons to attain the nearest inert gas configuration. Mercury is a non-metal that combines with fluorine which is a non-metal forms a compound with molecular formula of \[H{g_2}{F_2}\] , the nomenclature can be written based on the oxidation state of central metal atom.

Complete answer:
Chemical elements are of two types based on nature. These are metals, and nonmetals. Metals can easily undergo loss of electrons, and non-metals can try to attract or gain electrons to attain the nearest inert gas configuration. As the inert gases have stable configuration.
Mercury is a non-metal with the chemical symbol \[Hg\], it is having less electronegativity compared to fluorine, where fluorine is the most electronegative element in the periodic table.
Mercury combines with fluorine to form different compounds like \[H{g_2}{F_2}\] and \[HgF\] . but mostly mercury exists as the \[H{g_2}^{2 + }\] only. In the compound \[H{g_2}{F_2}\] , the cation is \[H{g_2}^{2 + }\] .
The empirical formula of \[H{g_2}{F_2}\] is \[HgF\] .
In \[H{g_2}{F_2}\] mercury is the least electronegative element and occupies the central position and fluorine occupies the terminal positions.
The oxidation state of mercury in \[H{g_2}{F_2}\] will be \[2x + 2\left( { - 1} \right) = 0 \Rightarrow x = + 1\]
Thus, the oxidation state of mercury is represented as (I) which means the representation of oxidation number in roman numerals within brackets.
Thus, the nomenclature with Mercury (I) Fluoride is \[H{g_2}{F_2}\] but not \[HgF\]

Note:
Molecular formula is the representation of all the atoms arranged in the compound. Whereas empirical formula is the shortest representation of the atoms present in the molecular formula. In \[H{g_2}{F_2}\] the atoms are in the ratio \[2:2\] , in \[HgF\] the atoms are in \[1:1\] ratio, which is the shortest mole ratio.