Question

Write the chemical formulae of the following:

(a) Magnesium chloride

Answer 1

Chemical formulae

• A chemical formula is a formula that represents an element's quantitative proportion in a compound.
• Example: Water has the chemical formula ${\mathrm{H}}_2\mathrm{O}$, indicating that it is a compound made up of two parts of hydrogen and one proportion of oxygen.

Magnesium chloride

• Magnesium has a tendency to release two electrons.
• One electron is willing to be taken in by chlorine.
• To complete the octet, two chlorine atoms are required to take the two electrons from magnesium.
• The cation is ${\mathrm{Mg}}^{2+}$, and anion is ${\mathrm{Cl}}^{-}$ in magnesium chloride.

Formula for Magnesium chloride

• So, the chemical formula of magnesium chloride is ${\mathrm{MgCl}}_2$.