Thiols are compounds that contain an -SH functional group - Scottish Highers Chemistry - Question 6 - 2019

Propan-1-ol has a higher boiling point than ethanethiol due to the presence of stronger hydrogen bonds in propan-1-ol, which require more energy to break. In contrast, ethanethiol primarily exhibits weaker London dispersion forces. Therefore, to vaporize propan-1-ol, more energy is needed to overcome these forces compared to ethanethiol.

The thiol that contains only one carbon atom is methanethiol.

To calculate the minimum mass, use the formula:

\text{Concentration (mg/cm³)} = \frac{Mass (mg)}{Volume (cm³)}

Given that the volume of the room is 43,900 litres = 43,900,000 cm³ and the minimum concentration detectable is 2.7 × 10^-7 mg/cm³, we find the mass:

\text{Mass} = 2.7 imes 10^{-7} imes 43,900,000 = 0.0119 ext{ mg}.

Thus, the minimum mass is approximately 0.0119 mg of ethanethiol.

2-methyl-2-propanethiol is classified as a tertiary thiol because the sulfur atom is bonded to a carbon atom that is connected to three other carbon atoms.

The other isomer formed in this addition reaction is 2-propanethiol, which can be represented structurally as follows:

  H     H
  |     |
  H-C-S-H
  |     |
  H     C-H
        |   H
        H

The theoretical mass of 2-methyl-2-propanethiol that can be produced from 30.5 g of 2-methylpropene with a GFM of 90 g is:

\text{Theoretical mass} = 30.5 ext{ g} imes \frac{90 ext{ g}}{56 ext{ g}} = 48.85 ext{ g}.

Given the chemist achieved an 84% yield, the actual mass produced is:

\text{Actual mass} = 0.84 imes 48.85 ext{ g} = 41.0 ext{ g}.

Thus, the mass of 2-methyl-2-propanethiol made is approximately 41.0 g.