Chemistry - CHEMICAL BONDING Question with Solution | TestHub

Option A: ${\mathrm{CO}}_2,{\mathrm{C}}_2{\mathrm{H}}_4,\mathrm{NO}$ and HCl 1. ${\mathrm{CO}}_2$ : Carbon dioxide follows the octet rule. Carbon forms double bonds with two oxygen atoms, allowing it to have 8 electrons in its valence shell. 2. ${\mathrm{C}}_2{\mathrm{H}}_4$ : Ethylene follows the octet rule. Each carbon forms a double bond with the other carbon and single bonds with two hydrogen atoms, resulting in 8 electrons in the valence shell of the carbons. 3. NO: Nitric oxide does not follow the octet rule. It has an odd number of electrons, making it a free radical. 4. HCl: Hydrogen chloride follows the octet rule. Chlorine has 8 electrons in its valence shell when bonded with hydrogen. Thus, three molecules ${\mathrm{CO}}_2,{\mathrm{C}}_2{\mathrm{H}}_4$, and HCl follow the octet rule here. Option B: ${\mathrm{NO}}_2,{\mathrm{O}}_3,\mathrm{HCl}$ and ${\mathrm{H}}_2{\mathrm{SO}}_4$ 1. ${\mathrm{NO}}_2$ : Nitrogen dioxide does not follow the octet rule. It has an odd number of electrons. 2. ${\mathrm{O}}_3$ : Ozone follows the octet rule. It has a resonance structure that allows each oxygen atom to have 8 electrons in its valence shell. 3. HCl: As mentioned, hydrogen chloride follows the octet rule. 4. ${\mathrm{H}}_2{\mathrm{SO}}_4$ : Sulfuric acid follows the octet rule. All atoms achieve stable configurations through bonding. Thus, three molecules ${\mathrm{O}}_3,\mathrm{HCl}$, and ${\mathrm{H}}_2{\mathrm{SO}}_4$ follow the octet rule in this option. Option C: ${\mathrm{BCl}}_3,{\mathrm{NO}}_2,{\mathrm{NO}}_2$ and ${\mathrm{H}}_2{\mathrm{SO}}_4$ 1. ${\mathrm{BCl}}_3$ : Boron trichloride does not follow the octet rule. Boron has only 6 electrons in its valence shell. 2. NO: As mentioned, nitric oxide does not follow the octet rule. 3. ${\mathrm{NO}}_2$ : As mentioned, nitrogen dioxide does not follow the octet rule. 4. ${\mathrm{H}}_2{\mathrm{SO}}_4$ : Sulfuric acid follows the octet rule. Thus, only one molecule, ${\mathrm{H}}_2{\mathrm{SO}}_4$. follows the octet rule in this option. Option D: ${\mathrm{CO}}_2,{\mathrm{BCl}}_3,{\mathrm{O}}_3$ and ${\mathrm{C}}_2{\mathrm{H}}_4$ 1. ${\mathrm{CO}}_2$ : As mentioned, carbon dioxide follows the octet rule. 2. ${\mathrm{BCl}}_3$ : As mentioned, boron trichloride does not follow the octet rule. 3. ${\mathrm{O}}_3$ : As mentioned, ozone follows the octet rule. 4. ${\mathrm{C}}_2{\mathrm{H}}_4$ : As mentioned, ethylene follows the octet rule. Thus, three molecules ${\mathrm{CO}}_2,{\mathrm{O}}_3$, and ${\mathrm{C}}_2{\mathrm{H}}_4$ follow the octet rule in this option. Conclusion: The correct options are Option A and Option D, both having at least three molecules that follow the octet rule.