Question

Write the chemical formula for the covalent compounds and mention the molecular weight after the formula

Carbon disulphide

Answer 1

Covalent compound

• Covalent compounds are compounds having strong intramolecular bonds. atoms within the compound are tightly held together
• A covalent bond is formed by sharing of electron pairs between atoms. these electron pairs are known as shared pairs or bonding pairs.

Carbon disulfide

• Carbon disulfide contains one carbon atom and ‘di’ means 2, so two sulfur atoms are present in the molecule
• Carbon has a valency of 4 and sulfur has 2

$$\begin{gathered} \mathrm{C}\mathrm{S} \\ 42(\mathrm{crossmultiply}\mathrm{the}\mathrm{valencies}\mathrm{as}\mathrm{their}\mathrm{subscripts}) \\ {\mathrm{C}}_2{\mathrm{S}}_4(\mathrm{simplifying}\mathrm{the}\mathrm{ratio}\mathrm{of}\mathrm{atoms}) \\ {\mathrm{CS}}_2 \end{gathered}$$

• The chemical formula for Carbon disulfide is ${\mathbf{CS}}_{\mathbf{2}}$

Molecular weight

• Mass of C - 12
• Mass of S - 32
• Molecular weight of ${\mathrm{CS}}_2$ = 12 + (2 x 32) = 76 g