Heating phenol with zinc dust leads to the conversion of phenol to benzene. Zinc acts as a reducing agent, facilitating this transformation.

The Reimer-Tiemann reaction involves treating phenol with chloroform in the presence of sodium hydroxide, resulting in the introduction of a -CHO group at the ortho position of the benzene ring. The intermediate benzal chloride is hydrolyzed to produce salicylaldehyde.

Methanol is mainly produced through the catalytic hydrogenation of carbon monoxide, utilizing a ZnO – Cr₂O₃ catalyst. It is used as a solvent in paints, varnishes, and predominantly in the production of formaldehyde.

Cr has a configuration of 3d⁵ 4s¹ instead of 3d⁴ 4s², and Cu has 3d¹⁰ 4s¹ instead of 3d⁹ 4s². The small energy gap between 3d and 4s orbitals prevents electrons from entering the 3d orbitals, contributing to these unique ...

Exceptions arise due to minimal energy differences between (n-1)d and ns orbitals. Half and completely filled sets of orbitals are more stable, leading to anomalies like Cr having a configuration of 3d⁵ 4s¹ instead of 3d⁴ 4s².