Question

How do you write the formula of zinc oxide?

Answer 1

Chemical formula:-

• In a chemical compound, the symbolic representation of the composition is known as its chemical formula.
• A chemical formula of a compound gives us information about the number of particular elements and also enables us to figure out the kind of element present and in what proportion, etc.

Formation of chemical formula:-

• Knowing about the valence electrons and valencies, are very important for the formation of chemical compounds
• The valence electrons present in the outermost shell reacts with the valence electrons in the outermost shell of another atom.
• The valencies determine the capacity of an atom to make bonds, with the help of the valence electron present.
• Let us consider 2 elements X and Y, having valency 1 and 2 respectively.
• Therefore, the formation of chemical formula will be like this:

• Therefore, the chemical formula of the compound formed is ${\mathrm{X}}_2{\mathrm{Y}}_1$

Chemical formula of Zinc oxide:-

• Electronic configuration of Zinc is $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{6}3{\mathrm{s}}^{2}3{\mathrm{p}}^{6}4{\mathrm{s}}^{2}3{\mathrm{d}}^{10}$and while reaction, the 2 valence electrons from the 4s orbital take part in the reaction.
• Hence valency of Zinc is $2$.
• Electronic configuration of Oxygen is $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^4$and has a valency of 2.
• Two oxygen atoms reacts with the two valence electrons of the zinc atom to form the compound $\mathrm{ZnO}$.
• Therefore, the formation of the chemical formula will be like this:

• Here since both the elements have a valency of 2, so the formula ${\mathrm{Zn}}_2{\mathrm{O}}_2$ can be simply written as $\mathrm{ZnO}$ by taking 2 common and canceling it.

Therefore, the chemical formula of Zinc oxide is $\mathrm{ZnO}$