Question

Identify the incorrect statement from the following:

• A. \(ECl_3\), \((E=B \text{ and } Al)\), is a monomer when \(E=B\) and a dimer when \(E=Al\).
• B. The order of catenation property of Group 14 elements is \(C >> Si>Ge = Sn\).
• C. Oxygen exhibits only \(-2\) oxidation state.
• D. Carbon has the ability to form \(p\pi-p\pi\) multiple bond with itself.

Hint:

Oxygen commonly shows \(-2\), but it can also show \(-1\), \(-\frac{1}{2}\), \(+1\), and \(+2\) oxidation states in special compounds.

Answer 1

The Correct Option is C

To identify the incorrect statement, we need to analyze the properties and behaviors of the chemical elements mentioned:

1. \(ECl_3\), \((E=B \text{ and } Al)\), is a monomer when \(E=B\) and a dimer when \(E=Al\):
   • Boron chloride \((BCl_3)\) indeed forms a monomer because it is a small molecule with complete octet structure without any need for dimerization through additional bonds.
   • Aluminum chloride \((AlCl_3)\), however, tends to dimerize \((Al_2Cl_6)\) to satisfy the electron deficiency in aluminum.
2. The order of catenation property of Group 14 elements is \(C >> Si > Ge = Sn\):
   • Catenation refers to the ability of an element to form chains with itself.
   • Carbon shows the highest catenation property due to its small size and tetra-valency.
   • Silicon shows significant, but lesser catenation, followed by Ge and Sn which have limited ability.
3. Oxygen exhibits only \(-2\) oxidation state:
   • This statement is incorrect. While oxygen commonly exhibits a \(-2\) oxidation state, it can also exhibit \(-1\) in peroxides (e.g., \(H_2O_2\)) and \(0\) as in O\(_2\).
4. Carbon has the ability to form \(p\pi-p\pi\) multiple bond with itself:
   • This is true. Carbon atoms can form double and triple bonds through \(p\pi-p\pi\) overlap, creating compounds like alkenes and alkynes.

Therefore, the incorrect statement is that "Oxygen exhibits only \(-2\) oxidation state."