Question

Molecular weight of phenol is:
(A) 94.11
(B) 104.11
(C) 86.11
(D) 98

Answer 1

Hint: Phenol is an aromatic organic compound with the molecular formula \[{C_6}{H_5}OH\]. It is a white crystalline solid that is volatile. The molecule consists of a phenyl group bonded to a hydroxyl group.

Complete step by step answer:
The molecular weight is the sum of the atomic weights of the atoms in the molecule. The molecular formula of phenol is \[{C_6}{H_5}OH\].
- Atomic weight of carbon is 12
- Atomic weight of hydrogen is 1
- Atomic weight of oxygen is 16
So, adding the atomic weights of all the atoms that forms phenol, we get,
Molecular weight of phenol is \[ = 6\left( {12} \right) + 5\left( 1 \right) + 16 + 1\] \[ = 94.11\]
Hence, the molecular weight of Phenol is 94.11. So, the correct option is (A)

Additional information: Phenols are similar to alcohols but form stronger hydrogen bonds. Thus, they are more soluble in water than are alcohols and have higher boiling points. Phenols occur either as colourless liquids or white solids at room temperature and may be highly toxic and caustic. Phenols are widely used in household products and as intermediates for industrial synthesis. Phenol is used (in low concentrations) as a disinfectant in household cleaners and in mouthwash.

Note: Molecular weight of a compound is often confused with molar mass. The molar mass of a chemical compound is defined as the mass of a sample of that compound divided by the amount of substance in that sample, measured in moles. While molecular weight is the sum of the atomic weights of the atoms in the molecule.