Chapter 24, Problem 24.17P

a)

Interpretation Introduction

Interpretation:

From the Table 24-2, the elution order of Hexane, Heptane, Octane, Benzene, Butanol and 2-pentanone has to predicted from the column containing Poly(dimethylsiloxane).

Concept Introduction:

Kovats retention index:

Retention index, I for linear alkane equals 100 times the number of Carbon atoms.

For a molecule of Octane, $\text{I=800}$

For a molecule of Nonane, $\text{I=900}$

The elution of compound between Octane and Nonane will have retention index between 800 and 900 is calculated using the formula,

$\text{I=100}\left[\text{n+}\left(\text{N-n}\right)\frac{\text{log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{unknown}\right)\text{-log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{n}\right)}{\text{log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{N}\right)\text{-log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{n}\right)}\right]$

Where, $\text{n}$= number of Carbon atoms in smaller alkane

$\text{N}$ = number of Carbon atoms in larger alkane

${\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{n}\right)$ = adjusted retention time of smaller alkane

${\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{N}\right)$ = adjusted retention time of larger alkane

To predict the elution order of Hexane, Heptane, Octane, Benzene, Butanol and 2-pentanone from the column containing Poly(dimethylsiloxane)

b)

Interpretation Introduction

Interpretation:

From the Table 24-2, the elution order of Hexane, Heptane, Octane, Benzene, Butanol and 2-pentanone has to predicted from the column containing ${\left(\text{diphenyl}\right)}_{\text{0}\text{.35}}\text{,}{\left(\text{dimethyl}\right)}_{\text{0}\text{.65}}\text{polysiloxane}$.

Concept Introduction:

Kovats retention index:

Retention index, I for linear alkane equals 100 times the number of Carbon atoms.

For a molecule of Octane, $\text{I=800}$

For a molecule of Nonane, $\text{I=900}$

The elution of compound between Octane and Nonane will have retention index between 800 and 900 is calculated using the formula,

$\text{I=100}\left[\text{n+}\left(\text{N-n}\right)\frac{\text{log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{unknown}\right)\text{-log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{n}\right)}{\text{log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{N}\right)\text{-log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{n}\right)}\right]$

Where, $\text{n}$= number of Carbon atoms in smaller alkane

$\text{N}$ = number of Carbon atoms in larger alkane

${\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{n}\right)$ = adjusted retention time of smaller alkane

${\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{N}\right)$ = adjusted retention time of larger alkane

To predict the elution order of Hexane, Heptane, Octane, Benzene, Butanol and 2-pentanone from the column containing ${\left(\text{diphenyl}\right)}_{\text{0}\text{.35}}\text{,}{\left(\text{dimethyl}\right)}_{\text{0}\text{.65}}\text{polysiloxane}$

c)

Interpretation Introduction

Interpretation:

From the Table 24-2, the elution order of Hexane, Heptane, Octane, Benzene, Butanol and 2-pentanone has to predicted from the column containing poly(ethylene glycol).

Concept Introduction:

Kovats retention index:

Retention index, I for linear alkane equals 100 times the number of Carbon atoms.

For a molecule of Octane, $\text{I=800}$

For a molecule of Nonane, $\text{I=900}$

The elution of compound between Octane and Nonane will have retention index between 800 and 900 is calculated using the formula,

$\text{I=100}\left[\text{n+}\left(\text{N-n}\right)\frac{\text{log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{unknown}\right)\text{-log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{n}\right)}{\text{log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{N}\right)\text{-log}{\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{n}\right)}\right]$

Where, $\text{n}$= number of Carbon atoms in smaller alkane

$\text{N}$ = number of Carbon atoms in larger alkane

${\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{n}\right)$ = adjusted retention time of smaller alkane

${\text{t}}_{\text{r}}{}^{\text{'}}\left(\text{N}\right)$ = adjusted retention time of larger alkane

To predict the elution order of Hexane, Heptane, Octane, Benzene, Butanol and 2-pentanone from the column containing poly(ethylene glycol)