Question

The active ingredient in some oral anesthetics used in sore throat sprays. what is the molar mass of phenol?

Answer 1

Answer: Molecular mass of the phenol is 94g/mol.

Explanation:

Phenol is an active ingredient in some oral anesthetics used in sore throat sprays.It is used as anesthetics to cure minor sour throat pain , minor mouth irritations etc.

For Example : Cramex , Chloraseptic sprays contains phenol as an active ingredient.

Phenol has a molecular formula of $C_6H_5OH$

Molecular mass of the phenol = 6(mass of carbon)+5(mass of hydrogen)+1(mass of oxygen)+1(mass of hydrogen) = 6(12)+5(1)+1(16)+(1) = 94 g/mol

Answer 2

The molar mass of phenol is $\boxed{94.113{\text{ g/mol}}}$ .

Further Explanation:

Structure of phenol:

The phenol is a white crystalline aromatic compound which contains a hydroxyl group (-OH). Phenol is generally an active ingredient of phenol spray which helps in sore throat. It is also an active ingredient of some more oral analgesics which are used medically to reduce the pain.

The structure of phenol is composed of a benzene ring where one of the hydrogens is replaced by the –OH group. Since the molecular formula of benzene is ${{\text{C}}_6}{{\text{H}}_6}$ , therefore, after replacing of one hydrogen atom with –OH group, the molecular formula becomes,

$\begin{aligned}{\text{Molecular formula}}\left( {{\text{Phenol}}} \right)&= {\text{Benzene}}-{\text{H}}\left({{\text{one}}}\right)+{\text{OH}}\\&={{\text{C}}_{\text{6}}}{{\text{H}}_{\text{6}}} - {\text{H}}+{\text{OH}}\\&={{\text{C}}_{\text{6}}}{{\text{H}}_5}+{\text{OH}}\\&={{\text{C}}_{\text{6}}}{{\text{H}}_5}{\text{OH}}\\\end{aligned}$

Now calculate the molar mass of phenol as follows:

The formula to calculate the molar mass of phenol $\left({{{\text{C}}_{\text{6}}}{{\text{H}}_{\text{5}}}{\text{OH}}}\right)$ is,

${\text{Molar mass}}=\left[\begin{gathered}\left({{\text{Total number of C}}}\right)\left({{\text{Atomic mass of C}}}\right)+\hfill\\\left({{\text{Total number of H}}}\right)\left({{\text{Atomic mass of H}}}\right)+\hfill\\\left({{\text{Total number of O}}}\right)\left({{\text{Atomic mass of O}}}\right)\hfill\\\end{gathered}\right]$

The atomic mass of carbon atom is 12.011 g/mol.

The atomic mass of oxygen atom is 15.999 g/mol.

The atomic mass of hydrogen atom is 1.008 g/mol.

Substitute the respective values in the above formula,

Molar mass = [(Total number of C)(Atomic mass of C) + (Total number of H)(Atomic mass of H) + (Total number of O)(Atomic mass of O)]

$\begin{aligned}{\text{Molar mass}}&=\left[\begin{gathered}\left( {\text{6}}\right)\left({{\text{12}}{\text{.011 g/mol}}} \right)+\left({\text{6}} \right)\left({{\text{1}}{\text{.008 g/mol}}}\right)+\hfill\\\left({\text{1}} \right)\left({{\text{15}{\text{.999gmol}}}\right)\hfill\\\end{gathered}\right]\\&=94.113{\text{ g/mol}}\\\end{gathered}$

Therefore, the molar mass of phenol is 94.113 g/mol.

Learn more:

1. Balanced chemical equation: brainly.com/question/1405182

2. Stereoisomer for 1,2-difluoro-1,2-dimethylcyclopentane:brainly.com/question/8803065

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Mole concept

Keywords: Phenol, molar mass, moles, atomic mass, structure of phenol, benzene ring, hydrogen atoms, carbon atoms, benzene ring, OH group, 94.113 g/mol.