🧪Paper Chromatography - Chemistry Experiment with Mr Pauller

Summary

This video script details a chromatography experiment aimed at separating the pigments in a wet erase marker ink. By drawing a line on chromatography paper and submerging it in water, the pigments' different properties cause them to travel at varying speeds, resulting in a colorful separation. The experiment concludes with measuring pigment distances and calculating the Rf values to quantify their solubility and movement relative to water.

Takeaways

• 🔍 The experiment demonstrates chromatography to separate pigments in a wet erase marker ink.
• 🖊️ Wet erase markers contain water-soluble pigments, which are the subject of the separation.
• 📝 The process starts by drawing a line on chromatography paper with the marker.
• 🌊 The paper is then placed in a beaker with water, allowing capillary action to draw the water up the paper.
• ⏱️ The video is sped up to 16x to show the quick separation of pigments into different colors.
• 🎨 The original black ink separates into various pigments due to their distinct properties.
• 🏃‍♂️ Different pigments travel at different speeds because of their varying solubility and weight.
• 📏 Post-experiment, the distances traveled by each pigment and the water are measured for analysis.
• 📐 The measurement starts from a common point to ensure a fair comparison of pigment travel distances.
• 🌈 The maximum distance traveled by the water and each pigment is recorded for further calculations.
• 🔢 The Rf (retention factor) value is calculated for each pigment, with 1 indicating the same travel as water and 0.5 half that distance.

Q & A

What is the purpose of the chromatography experiment shown in the video?

The purpose of the experiment is to separate the different pigments of ink present in a wet erase marker using chromatography paper and water.

Why are the pigments in a wet erase marker water-soluble?

The pigments are water-soluble because wet erase markers are designed to be easily removed with water, which allows the pigments to dissolve and separate during the experiment.

How does the water cause the ink to separate on the chromatography paper?

The water rises up the chromatography paper due to capillary action, carrying the ink pigments with it and causing them to separate based on their different properties.

What factors determine the speed at which the pigments travel up the paper?

The speed at which the pigments travel is determined by their differing properties such as weight, solubility in water, and density.

Why does the ink appear black before the experiment begins?

The ink appears black because the different pigments are mixed together and not separated, creating the appearance of a single black color.

What is the significance of measuring the distance traveled by each pigment?

Measuring the distance traveled helps in analyzing the results of the experiment, as it allows for the comparison of how far each pigment has moved relative to the water.

How should the distances be measured for a fair comparison?

For a fair comparison, all distances should be measured starting from the same point where the pigments began traveling, ensuring that the starting point for water and pigments is consistent.

What is the Rf (retention factor) value and how is it calculated?

The Rf value is a measure used in chromatography to indicate the distance a pigment has traveled relative to the solvent. It is calculated by dividing the distance traveled by the pigment by the distance traveled by the water.

What would be the Rf value for a pigment that travels the same distance as the water?

The Rf value for a pigment traveling the same distance as the water would be 1, indicating that it has moved with the solvent front.

What would the Rf value indicate about a pigment if it were 0.5?

An Rf value of 0.5 would indicate that the pigment has traveled only half the distance of the water, suggesting it is less soluble or more dense than the other pigments.

Outlines

00:00

🧪 Chromatography Experiment Introduction

This paragraph introduces a chromatography experiment designed to separate pigments from a wet erase marker ink. The experiment utilizes chromatography paper and water to demonstrate the separation process due to the pigments' different properties, such as solubility and weight. The video is sped up to show the quick separation into various colors, highlighting the principle behind the experiment.

Keywords

💡Chromatography

Chromatography is a method used to separate mixtures into their individual components based on their different affinities to the stationary and mobile phases. In the context of the video, the chromatography experiment is used to separate the pigments in ink, demonstrating how different pigments travel at varying speeds due to their unique properties, which is central to the video's theme of pigment separation.

💡Pigments

Pigments are substances that give color to various materials through selective absorption and reflection of light. In the video, the pigments in a wet erase marker ink are separated using chromatography, showing that what appears as black ink is actually a mixture of different pigments that can be individually identified and distinguished.

💡Wet Erase Marker

A wet erase marker is a type of pen that contains water-soluble ink, which can be easily wiped off from surfaces like whiteboards. The script mentions using a wet erase marker for the experiment, emphasizing that its pigments are water-soluble, a key property for the chromatography process depicted in the video.

💡Chromatography Paper

Chromatography paper is a type of thin, porous material that is used in chromatographic techniques to separate the components of a mixture. In the video, the paper is used to draw a line of ink, which then serves as the sample for the chromatography experiment, allowing the different pigments to be separated as the water travels up the paper.

💡Capillary Action

Capillary action is the ability of a liquid to flow in narrow spaces without the assistance of external forces like gravity. In the script, it is mentioned as the reason why water quickly rises up the chromatography paper, demonstrating a fundamental principle that drives the separation process in the experiment.

💡Solvent

A solvent is a substance, usually a liquid, that has the ability to dissolve other substances. In the context of the video, water acts as the solvent or mobile phase in the chromatography experiment, interacting with the pigments and causing them to move up the paper at different rates.

💡Rf Value (Retention Factor)

The Rf value, or retention factor, is a measure used in chromatography to quantify the interaction between the compound of interest and the stationary phase. In the video, it is used to analyze the results of the pigment separation, with an Rf value of 1 indicating the pigment traveled the same distance as the solvent, and lower values indicating less movement relative to the solvent.

💡Mobile Phase

The mobile phase in chromatography is the phase that moves through the stationary phase, carrying the components of the mixture to be separated. In the video, water serves as the mobile phase, causing the pigments to separate based on their different affinities for the water and the stationary phase (chromatography paper).

💡Stationary Phase

The stationary phase in chromatography is the phase that remains fixed in place while the mobile phase moves through it. In the video, the chromatography paper represents the stationary phase, providing a surface on which the pigments can interact with the mobile phase (water) and separate.

💡Separation

Separation in the context of the video refers to the process of distinguishing and isolating the different pigments within the ink through chromatography. The goal of the experiment is to achieve this separation, which is visually demonstrated as the ink's pigments move at different speeds and eventually form distinct bands on the paper.

💡Analysis

Analysis in this script refers to the process of examining and interpreting the results of the chromatography experiment. It includes measuring the distances traveled by the pigments and the water, and calculating the Rf values to understand the separation of the pigments, which is a key step in demonstrating the effectiveness of the chromatography technique.

Highlights

The experiment aims to separate different pigments in wet erase marker ink using chromatography.

Wet erase markers contain water-soluble pigments.

Chromatography paper is used to draw a line with the marker ink.

The paper is inserted into a beaker with water to observe capillary action.

Capillary action causes the water to rise quickly, as shown in the 16x speed playback.

Ink separation into different colors is observed due to varying pigment properties.

Pigments with different solubility and weight travel at different speeds during chromatography.

The experiment concludes with the separation of pigment colors.

Analysis involves measuring the distance traveled by each pigment.

Fair comparison requires measuring from the same starting point for both water and pigments.

The maximum distance traveled by water and pigments is measured for analysis.

The playback continues to demonstrate the final pigment separation.

The Rf (retention factor) value is calculated for each pigment color.

An Rf value of 1 indicates a pigment travels the same distance as the water.

An Rf value of 0.5 suggests a pigment travels half the distance of the water.

The Rf value helps in understanding the relative movement of pigments in the chromatography process.

Transcripts

This video shows an example of a chromatography experiment. The goal of

the experiment is to separate the different pigments of ink which are

present in a wet erase marker which we'll see right here. So a Vi- a-Vis

marker is wet erase which means that the pigments are water-soluble.

We'll start our experiment by drawing a line with the marker on the

chromatography paper. Then what we want to do is insert that chromatography

paper into a beaker with a small volume of water in it. We can see that the water

will start to rise up the chromatography paper because of capillary action. You'll

note that it's happening very quickly because this is 16x speed playback

we can see that the ink which originally looked black is starting to

separate into different colors. This is because the different pigments have

different properties - some of them are heavier, some are lighter, some are more

soluble in water, some are less. Because of these differing properties all of the

different colors are going to travel at different speeds. By the completion

of our experiment we should see some very nice separation of the different

pigment colors. Now to do analysis of our results what we're going to want to do

is to measure the distance travelled by each pigment. Let's pause here for a

moment, so I want to measure the maximum distance traveled by the water and then

by each different pigment starting at the line drawn on the paper. To be fair

we should be comparing the distance traveled by the water starting from the

same point where the pigments started traveling. So we'll measure all of our

distances starting at this point. Looks like the maximum distance traveled by

the water reaches about to here and then we can measure the maximum distance

traveled by each of the different pigments. Let's continue our playback

The final part of our analysis will be to calculate an Rf (retention factor) value. This is going

to be a different calculated number for each different color pigment. For a

pigment which travels exactly the same distance traveled by water, which is the

solvent (or the mobile phase) in this experiment the Rf value would calculate

to be 1 that's because the distance traveled by the pigment would be the

same as the distance traveled by the water. If we had a pigment color which

travels half the distance of the water the RF value for that pigment would be

0.5