Chapter 21, Problem 93A

Interpretation Introduction

Interpretation:

The information given in the table needs to be drawn in graph and then the boiling and melting point of 11- and 12-carbon alkanes should be determined.

Concept introduction:

The temperature at which a liquid substance becomes gas is said to be boiling point. At this temperature, the pressure surrounding the liquid and vapor pressure of the liquid becomes equal.

The temperature at which a solid substance becomes liquid is said to be melting point. At this temperature, the solid and liquid phases exist in equilibrium.

Explanation of Solution

Given:

The table:

From the given table, it can be observed that with increase in number of C atoms in alkane, the melting and boiling point increases.

The graph between melting and boiling point and number of C atoms in alkane where y-axis represents temperature and x-axis represents number of C atoms in alkane is:

Now, the boiling and melting point of 11- and 12-carbon alkanes can be predicted by extrapolating the best fit line as:

For C-11 boiling point and melting point is approximately ${\text{205 }}^{\text{o}}\text{C}$ and ${\text{-25 }}^{\text{o}}\text{C}$ respectively and actual value is ${\text{196 }}^{\text{o}}\text{C}$ and ${\text{-26 }}^{\text{o}}\text{C}$ respectively.

For C-12 boiling point and melting point is approximately ${\text{220 }}^{\text{o}}\text{C}$ and ${\text{-10 }}^{\text{o}}\text{C}$ respectively and actual value is $\text{216}{\text{.2 }}^{\text{o}}\text{C}$ and ${\text{-10 }}^{\text{o}}\text{C}$ respectively.