Chapter 28, Problem 28.7QAP

Interpretation Introduction

(a)

Interpretation:

The definition of the isocratic elution is to be stated.

Concept introduction:

The elution is the method of extracting the material from other material in the organic or analytical chemistry. There are various types of elution in the chromatography.

Answer to Problem 28.7QAP

The elution which has only a single solvent or stable ratio of the solvent mixture is called the isocratic elution.

Explanation of Solution

The isocratic elution is the type of elution in the chromatography. The basic use of the elution is extraction of one material from another material. The elution which has only a single solvent or stable ratio of the solvent mixture is called the isocratic elution. In this elution the same mobile phase is used throughout the process. The mixture of the mobile phase is remains consistent during complete process of testing.

Thus, the isocratic elution has only a single solvent or stable ratio of the solvent mixture.

Interpretation Introduction

(b)

Interpretation:

The definition of the gradient elution is to be stated.

Concept introduction:

The elution is the method of extracting the material from other material in the organic or analytical chemistry. There various types of elution in the chromatography.

Answer to Problem 28.7QAP

The elution which has two or more solvent with different polarity and varied composition during the process is known as gradient elution.

Explanation of Solution

The gradient elution is the type of elution in the chromatography. The basic use of the elution is extraction of one material from another material. The gradient elution is defined as the elution which consist two or more solvent which are differ in the polarity and also varied in composition during the separation. In this elution the strength of the solvent is increased in mobile phase during the process. The mixture of the mobile phase is not remains consistent during complete process of testing.

Thus, the elution which has two or more solvent with different polarity and varied composition during the process is known as gradient elution.

Interpretation Introduction

(c)

Interpretation:

The definition of the stop flow injection is to be stated.

Concept introduction:

There is several injection methods used for injecting the different types of samples into the heads of the column of respective samples.

Answer to Problem 28.7QAP

The stop flow injection is a method in which the sample is directly injected into the head of the column during the stoppage of the mobile phase flow.

Explanation of Solution

The stop flow injection is a method of injecting the sample directly into the head of the column. The flow of the mobile phase is stopped for a short period of time to inject the sample directly into the head of the column. This method of injecting is known as the stop flow injection.

Thus, the stop flow injection is a method in which the sample is directly injected into the head of the column during the stoppage of the mobile phase flow.

Interpretation Introduction

(d)

Interpretation:

The definition of the reversed phase packing is to be stated.

Concept introduction:

The reversed-phase packing is a packing in which the bonded phase are non polar in nature and solute are polar in nature. The compounds with greater polarity are responsible for the attraction towards the reverse-phase packing more as compared to the compound with the less polarity.

Answer to Problem 28.7QAP

The reversed-phase packing is defined as the packing in which the bonded phase are non polar in nature and solute are polar in nature. The order of each compound depends on the polarity of the compounds. The greater polarity of compounds is also responsible for the greater elution.

Explanation of Solution

The bonded phase has non polar nature in the reversed-phase packing. The non polar solute attracted towards the reverse phase packing and spent more time on the non polar bonded packing. Due to this the non-polar solute elute at the last. The polar solute will not attracted towards the bonded packing and also elute first from the column. The order of each compound depends on the polarity of the compounds. The greater polarity of compounds is also responsible for the greater elution.

Thus, the reversed-phase packing is defined as the packing in which the bonded phase are non polar in nature and solute are polar in nature. The order of each compound depends on the polarity of the compounds. The greater polarity of compounds is also responsible for the greater elution.

Interpretation Introduction

(e)

Interpretation:

The definition of the normal phase packing is to be stated.

Concept introduction:

The normal phase packing chromatography is the type of packing in the chromatography in which mobile phase is non-polar in nature and the stationary phase is polar in nature.

Answer to Problem 28.7QAP

The packing in the chromatography in which mobile phase is non-polar in nature and the stationary phase is polar in nature is known as the normal phase packing chromatography.

Explanation of Solution

The mobile phase is non-polar in nature and the stationary phase is polar in nature in the normal phase packing chromatography. The compound which has the most polar nature will put at the last. And the compound with the less polarity is placed at the first stage of the group. The order of each compound depends on the polarity of the compounds. The compounds with more polarity will place at the last stage in the elution order and vice versa. This packing is just opposite to the reverse-phase packing.

Thus, the packing in the chromatography in which mobile phase is non-polar in nature and the stationary phase is polar in nature is known as the normal phase packing chromatography.

Interpretation Introduction

(f)

Interpretation:

The definition of the ion-pairing chromatography is to be stated.

Concept introduction:

The chromatography is the method of separation of the mixtures of the substances in their compounds. There are various forms of chromatography and all works on the same principle. The mobile phase of the compounds flows through the stationary phase of the compounds and carries the mixture of components along with it.

Answer to Problem 28.7QAP

The ion-pairing chromatography is a technique used for the separation of the partly ionized organic ions and the organic ions. In the technique some specific ion-pairing reagent is added in the mobile phase of the chromatography.

Explanation of Solution

The ion-pairing chromatography is a technique used for the separation of the partly ionized organic ions and the organic ions. This technique is also known as the reversed-phase liquid chromatographic technique. In the technique some specific ion-pairing reagent is added in the mobile phase of the chromatography. These reagents are large organic counter-ion. The analyte molecules adhere on the organic counter −ion as a result of the adsorption or electrostatic force.

Thus, the ion-pairing chromatography is a technique used for the separation of the partly ionized organic ions and the organic ions. In the technique some specific ion-pairing reagent is added in the mobile phase of the chromatography.

Interpretation Introduction

(g)

Interpretation:

The definition of the ion chromatography is to be stated.

Concept introduction:

The chromatography is the method of separation of the mixtures of the substances in their compounds. There are various forms of chromatography and all works on the same principle. The mobile phase of the compounds flows through the stationary phase of the compounds and carries the mixture of components along with it.

Answer to Problem 28.7QAP

The ion chromatography is also a separation technique used to separate the polar molecules and ions. This separation process is based on the affinity of the ions and polar molecules to the ion exchange.

Explanation of Solution

The ion chromatography is also a separation technique used to separate the polar molecules and ions. This separation process is based on the affinity of the ions and polar molecules to the ion exchange. This is very useful technique and used for various compounds such as large proteins, amino acids and small nucleotides. The ion chromatography is also known as ion-exchange chromatography. In this method the stationary phase is an ion-exchange resin and a normal detector is used to detect the analyte.

Thus, the ion chromatography is also a separation technique used to separate the polar molecules and ions. This separation process is based on the affinity of the ions and polar molecules to the ion exchange.

Interpretation Introduction

(h)

Interpretation:

The definition of the bulk property detector is to be stated.

Concept introduction:

The bulk property detector is a universal detector and used to measure properties. It can measure the properties in mobile phase with or without the presence of the sample.

Answer to Problem 28.7QAP

The bulk property detector is a universal detector used to respond about the bulk properties of the mobile phase which are modified due to the presence of solute.

Explanation of Solution

The bulk property detector is used to measure the differences in the physical property of the solute in the mobile phase as compared to the mobile phase alone. The bulk property detector is a universal detector in HPLC. This is responsible to detect the physical bulk properties of the mobile phase such as density, dielectric constant and refractive index. These properties are modified due to presence of solute in the mobile phase.

Thus, the bulk property detector is a universal detector used to respond about the bulk properties of the mobile phase which are modified due to the presence of solute.

Interpretation Introduction

(i)

Interpretation:

The definition of the solute property detector is to be stated.

Concept introduction:

The solute property detector is a type of detector used to measure the properties of the solute.

Answer to Problem 28.7QAP

The solute property detector is a type of detector used to measure the properties of the solute. The properties measured by this detector are UV-absorbance, diffusion current and the fluorescence.

Explanation of Solution

The solute property detector is a type of detector used to measure the properties of the solute. The properties of the solute measured by the solute property detector are UV-absorbance, diffusion current and the fluorescence. These properties are not possessed by the mobile phase. There are two types of the solute property detector such as variable wavelength detector and fixed wavelength detector.

Thus, the solute property detector is a type of detector used to measure the properties of the solute. The properties measured by this detector are UV-absorbance, diffusion current and the fluorescence.

Interpretation Introduction

(j)

Interpretation:

The definition of the sparging is to be stated.

Concept introduction:

The sparging is a process used to remove the gases from the mobile phase for better analysis of the solute.

Answer to Problem 28.7QAP

The process of removing the dissolved gases from the mobile phase is known as the sparging

Explanation of Solution

The process of removing the dissolved gases from the mobile phase is known as the sparging. Some gases are not mixed in the solutions properly due to low solubility. Due to immiscible mixture the bubbles are formed in the solution. These bubbles are responsible for the incorrect analysis of the solute. Therefore, the sparging process is also used for the correct analysis of the solute in the mobile phase.

Thus, the process of removing the dissolved gases from the mobile phase is known as the sparging.