Question

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

Nitrogen Trichloride

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.

Nitrogen trichloride

• Nitrogen trichloride contains one nitrogen atom and 3 chlorine atom
• nitrogen has a valency of +3 and chlorine has a valency of -1

$$\begin{gathered} \mathrm{N}\mathrm{Cl} \\ 31(\mathrm{crossmultiply}\mathrm{the}\mathrm{valencies}\mathrm{as}\mathrm{their}\mathrm{subscripts}) \\ {\mathrm{NCl}}_3 \end{gathered}$$

• The chemical formula for Nitrogen trichloride is ${\mathbf{NCl}}_{\mathbf{3}}$

Molecular weight

• Mass of N - 14
• Mass of Cl - 35.5
• Molecular weight of ${\mathrm{NCl}}_3$ = 14 + (3 x 35.5) = 120.5 g