Paper Chromatography - MeitY OLabs

amritacreate

9 Feb 201706:41

Summary

TLDRThis video script outlines the process of paper chromatography, a technique used to separate colored components in mixtures. It details two experiments: one separating red and blue ink pigments and another isolating compounds from spinach leaf extract. The method involves using Whatman filter paper, a chromatographic chamber, and a solvent mixture of distilled water and isopropyl alcohol. The script instructs on applying the mixture to the filter paper, allowing the solvent to rise, and calculating the Rf values to measure the separation of pigments.

Takeaways

📝 Paper chromatography is a technique used to separate colored components in a mixture, such as red and blue inks or spinach leaf extract.
🖌️ A Whatman filter paper strip is used as the stationary phase in the chromatography process.
🔬 The mixture to be separated is applied at a specific point 'P' on the filter paper, which is above the solvent line once the experiment begins.
💧 A solvent mixture of distilled water and isopropyl alcohol is prepared and used in the chromatographic chamber.
📏 The filter paper is suspended in the chamber in such a way that the pencil line is about 2 cm above the solvent level.
🕒 The chamber is closed and left undisturbed to allow the solvent to rise and carry the components of the mixture with it.
🌈 As the solvent rises, it carries the different components of the mixture at varying rates, leading to their separation on the filter paper.
📏 The distance traveled by the solute and the solvent from the original line is measured to calculate the Rf values.
📐 Rf values are calculated using the formula R_f = (Distance traveled by the solute from the original line) / (Distance traveled by the solvent from the original line).
🔍 The Rf values help in identifying and comparing the components separated by paper chromatography.
🌿 The script also describes a similar process for separating pigments from spinach leaf extract, indicating the versatility of paper chromatography for different mixtures.

Q & A

What is the purpose of paper chromatography as described in the script?
-Paper chromatography is used to separate colored components present in a mixture, such as the red and blue inks, and the pigments from spinach leaf extract.
What materials are needed to perform paper chromatography on red and blue inks as per the script?
-The materials needed include a mixture of red and blue inks, distilled water, isopropyl alcohol, Whatman filter paper strip, pencil, scale, capillary tube, and a chromatographic chamber.
How should the Whatman filter paper strip be prepared for the chromatography experiment?
-The Whatman filter paper strip should have a line drawn 4 cm from one end and another line drawn lengthwise from the center, intersecting at point P.
What is the significance of point P on the filter paper strip?
-Point P is where the mixture of red and blue inks, or the spinach leaf extract, is applied to the filter paper strip.
Why is the ink mixture applied twice to point P on the filter paper?
-The ink mixture is applied twice to ensure that the spot is rich in the mixture, which helps in the clear separation of the colored components during chromatography.
What is the solvent used in the chromatographic chamber and how is it prepared?
-The solvent is a mixture of distilled water and isopropyl alcohol, prepared by measuring 5 ml of each and mixing them in the chromatographic chamber.
How should the filter paper be positioned in the chromatographic chamber?
-The filter paper should be suspended vertically in the chamber with the pencil line about 2 cm above the solvent level.
What is the solvent front and how is it marked on the filter paper?
-The solvent front is the distance the solvent has risen on the filter paper. It is marked with a pencil line after the solvent has risen to about 15 cm.
How are the Rf values calculated for the separated components in the chromatography?
-The Rf values are calculated using the formula R_f = (Distance travelled by the solute from the original line) / (Distance travelled by the solvent from the original line).
What is the difference between the chromatography process for ink and spinach leaf extract as described in the script?
-The process is largely the same, with the main difference being the substance being tested: a mixture of red and blue inks versus the extract from spinach leaves.
Why is it important to let the filter paper dry after applying the ink or leaf extract?
-Allowing the filter paper to dry ensures that the mixture is absorbed properly and does not spread when the paper is handled, which could affect the accuracy of the chromatography results.

Outlines

00:00

🖌️ Paper Chromatography for Ink Separation

This section describes the process of separating colored components from a mixture of red and blue inks using paper chromatography. The necessary materials include red and blue ink mixture, distilled water, isopropyl alcohol, Whatman filter paper, a pencil, a scale, a capillary tube, and a chromatographic chamber. The procedure involves drawing lines on the filter paper, applying ink mixture at the intersection point, and allowing it to dry. The solvent is prepared by mixing distilled water and isopropyl alcohol in the chamber. The filter paper is suspended above the solvent, and the chamber is closed to allow the solvent to rise, carrying the ink components with it. The separation is observed as different colored spots on the paper, and the Rf values are calculated to quantify the separation.

05:08

🌿 Paper Chromatography for Spinach Pigment Separation

This paragraph outlines the steps for separating pigments from spinach leaf extract using paper chromatography. The required materials are similar to the previous paragraph, with the addition of spinach leaf extract. The process involves marking the filter paper, applying the extract at the marked point, and allowing it to dry. The solvent is prepared in the chromatographic chamber and the filter paper is suspended in it. As the solvent rises, it carries the pigments, which separate into different spots on the paper. The solvent front is marked, and the paper is dried. The Rf values of the spots are calculated to determine the effectiveness of the separation.

Mindmap

Keywords

💡Paper Chromatography

Paper chromatography is a method used to separate the components of a mixture based on their different solubilities in a solvent. It is a fundamental technique in analytical chemistry. In the context of the video, paper chromatography is used to separate colored components in ink and spinach leaf extracts. The process involves drawing a line on a Whatman filter paper strip, applying the mixture at a specific point, and then observing the movement of the components as the solvent rises.

💡Whatman Filter Paper Strip

A Whatman filter paper strip is a type of specialized paper used in chromatography due to its uniformity and low ash content. It provides a stable surface for the chromatographic process. In the video, the strip is used as the medium for the separation of colored components in the mixtures, with lines drawn on it to guide the application of the mixture and to measure the distance traveled by the solvent.

💡Solvent

A solvent is a substance that dissolves other substances to form a solution. In the video, a mixture of distilled water and isopropyl alcohol is used as the solvent to facilitate the separation of the colored components in the ink and spinach leaf extract. The solvent's ability to dissolve and carry the components up the filter paper is key to the chromatography process.

💡Capillary Tube

A capillary tube is a thin glass tube used for transferring small amounts of liquid, such as the mixtures of red and blue inks or spinach leaf extract. In the video, a capillary tube is used to apply the mixture to the filter paper at the designated point, ensuring a precise and controlled application of the sample.

💡Chromatographic Chamber

A chromatographic chamber is a container used to hold the solvent and the filter paper during the chromatography process. It is typically sealed to prevent evaporation of the solvent. In the video, the chamber is filled with the solvent mixture and the filter paper is suspended within it, allowing the solvent to rise and carry the components up the paper.

💡Mixture

A mixture in the context of the video refers to the combination of red and blue inks or the extract from spinach leaves that are to be separated. The mixture is applied to the filter paper and undergoes chromatography to separate its individual components based on their differing affinities for the solvent and the paper.

💡Spot

In chromatography, a 'spot' refers to the visible mark left by a component of the mixture as it is separated and travels up the filter paper. The video describes the application of the mixture to create a 'rich spot' at point P on the filter paper, which then separates into distinct spots as the solvent carries the components.

💡Rf Value

The Rf value, or retention factor, is a measure used in chromatography to quantify the distance a component travels relative to the solvent front. It is calculated using the formula R_f = (Distance travelled by the solute from the original line) / (Distance travelled by the solvent from the original line). The video explains how to calculate Rf values for the separated components of the mixtures.

💡Solvent Front

The solvent front refers to the leading edge of the solvent as it moves up the filter paper during chromatography. In the video, the solvent front is marked on the paper to determine the distance it has traveled, which is then used in the calculation of the Rf values for the separated components.

💡Isopropyl Alcohol

Isopropyl alcohol, also known as rubbing alcohol or isopropanol, is a common solvent used in chromatography due to its ability to dissolve a wide range of substances. In the video, it is mixed with distilled water to create the solvent used in the chromatographic separation of the ink and spinach leaf extract components.

💡Distilled Water

Distilled water is water that has been purified through distillation to remove impurities and minerals. It is used in the video as part of the solvent mixture for chromatography. The use of distilled water ensures that the solvent does not introduce additional contaminants that could affect the separation process.

Highlights

Separation of colored components in red and blue ink mixtures using paper chromatography.

Use of Whatman filter paper strip for chromatography.

Application of pencil to mark lines on the filter paper for sample application.

Utilization of capillary tube for transferring ink mixture to the filter paper.

Drying of ink mixture on filter paper in open air to prevent smudging.

Preparation of solvent mixture with distilled water and isopropyl alcohol.

Use of chromatographic chamber for the separation process.

Observation of solvent and ink rise on the filter paper.

Identification of red and blue ink spots after solvent front reaches 15 cm.

Marking the solvent front on the filter paper with a pencil.

Calculation of Rf values for red and blue inks using the distance traveled by the solute and solvent.

Separation of pigments from spinach leaf extract by paper chromatography.

Use of spinach leaf extract as a sample in the chromatography process.

Application of the same chromatography technique for different types of pigments.

Observation of different pigment spots on the filter paper after the solvent has risen.

Marking and measuring the distance of each pigment spot from the original line.

Calculation of Rf values for the components of spinach leaf extract.