Question

Fill in the blank spaces by choosing the correct words from the list given below:
List: Atom, analysis, formula, molecule, ferrous sulphide, air, physical, energy, heterogeneous, compound, dissolved

$\mathrm{FeS}$ is formula of ……………..

Answer 1

• The formula for the chemical FeS stands for iron(II) sulphide, also known as Ferrous sulphide.
• Iron (a transition metal) is represented by $\mathrm{Fe}$, and Sulphur is represented by $\mathrm{S}$ (a nonmetal).
• We can represent the formula by writing the symbols and then write the valency or charge.
• Interchange the valency/charge of the elements and write them as subscripts.

Element 1	Element 2
$\mathrm{Fe}$	$\mathrm{S}$
$2$	$2$

• Interchange the valency and write them as subscripts${\mathrm{Fe}}_2{\mathrm{S}}_2=\mathrm{FeS}$.
• Always express the atoms in the smallest ratio.

$\mathrm{FeS}$ is the formula of Ferrous sulphide.