Question

The following substances were separated on a gel filtration column. Estimate the molecular mass of the unknown.

Short answer

The molecular mass is MM =${10}^{5.5041}=319227.3$

Step-by-step solution

Define molecular mass:

Molecule mass is a molecular weight that is equal to the sum of all the atoms contained in a molecule.

Calculation for molecular mass of unknown:

First you need to make a graph in Excel or by hand in order to get the equation.

$y=-0.0631x+7.416$

Where y is log (MM) and x is${\mathrm{V}}_{\mathrm{r}}\left(\mathrm{mL}\right)$

Calculation for the value of y:

Next calculate the value of y which is log (MM) considering that${\mathrm{V}}_{\mathrm{r}}=30.3\mathrm{mL}$

$$\begin{gathered} \mathrm{y}=-0.0631\mathrm{x}+7.416 \\ \mathrm{y}=\left(-0.0631\times 30.3\right)+7.416 \\ \mathrm{y}=5.5041 \end{gathered}$$

Then we will calculate the molecular mass (MM)

$$\begin{gathered} \log \left(\mathrm{MM}\right)=5.5041 \\ \mathrm{MM}={10}^{5.5041}=319227.3 \end{gathered}$$