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Dec 10, 2025

4 pages

Understanding Paper Chromatography: Principles and Methods

Paper chromatography is a powerful technique used to separate chemical... Show more

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# PAPER CHROMATOGRAPHY
# CHE 4131 POST LAB

Chromatography

> involves physical separation of the different chemical substances in a mixture

Fundamentals of Paper Chromatography

Ever wonder how scientists can separate the components in a complex mixture like plant pigments? Paper chromatography is the answer! This technique uses filter paper as a solid support and separates components based on their different abilities to travel up the paper.

Paper chromatography works through partition rather than adsorption. The moisture trapped in the cellulose fibers of filter paper acts as the stationary phase, while an organic solvent serves as the mobile phase. The separation depends on factors like molecular structure, size, weight, and polarity of each compound.

There are two main types: paper adsorption chromatography wherepaperimpregnatedwithsilica/aluminaactsastheadsorbentwhere paper impregnated with silica/alumina acts as the adsorbent and paper partition chromatography (where moisture in paper fibers is the stationary phase). This technique is just one of many chromatographic methods, which include thin-layer chromatography (TLC), column chromatography, and high-performance liquid chromatography (HPLC).

Quick Tip: Paper chromatography is one of the most accessible chromatography techniques - that's why it's commonly used in school labs! You can separate complex mixtures with minimal equipment.

!DiagramshowingdifferentpigmentbandsseparatedbychromatographyDiagram showing different pigment bands separated by chromatography

# PAPER CHROMATOGRAPHY
# CHE 4131 POST LAB

Chromatography

> involves physical separation of the different chemical substances in a mixture

Materials and Sample Application

The paper used in chromatography matters more than you might think! Most experiments use Whatman filter paper, which contains 98-99% cellulose. The choice of paper depends on your sample, solvents, and whether you're doing qualitative or quantitative analysis.

Preparing your sample properly is crucial for good results. Solid samples must be dissolved in a suitable solvent before application. You'll typically apply your sample as a small spot on the "origin line" (the starting point on the paper). In some experiments, you might simply dip the paper directly into a solution containing your sample.

The mobile phase (solvent) choice depends entirely on what you're trying to separate. Scientists often use polar solvents like isopropanol, methanol, or water. If a single solvent doesn't work well, they might create a mixture to achieve better separation. The development happens in a chromatography chamber - usually a glass container that keeps the atmosphere saturated with solvent vapor.

Real-World Connection: The principles of paper chromatography are used in forensic science to analyze ink from crime scene documents. Different inks separate into distinct patterns, helping identify forgeries!

# PAPER CHROMATOGRAPHY
# CHE 4131 POST LAB

Chromatography

> involves physical separation of the different chemical substances in a mixture

Development Techniques and Visualization

The way you allow your chromatogram to develop can significantly impact your results. In ascending development, the solvent flows upward against gravity (most common in school labs). With descending development, the solvent flows downward, which is faster. There's even two-dimensional development where the paper is developed in one direction, then rotated and developed again - perfect for separating complex mixtures!

After development, the chromatogram needs to be dried with cold or hot air. But how do you see the separated components? If they're colored (like plant pigments), you can see them directly. For colorless substances, special visualization methods are needed. Physical methods include using iodine vapor or UV light, while chemical methods involve spraying reagents that react with specific compounds to produce color.

Scientists can perform both qualitative and quantitative analysis using paper chromatography. For quantitative work, they might compare spot intensity, use photo densitometry (measuring color density), or employ fluorimetry for fluorescent compounds. For particularly sensitive work, radioactive tracers can be used to detect extremely small amounts of material.

Pro Tip: When analyzing amino acids or proteins, ninhydrin spray is commonly used - it reacts with amino acids to produce distinctive purple or brown spots, making invisible compounds visible!

# PAPER CHROMATOGRAPHY
# CHE 4131 POST LAB

Chromatography

> involves physical separation of the different chemical substances in a mixture

RF Values and Applications

The most important measurement in paper chromatography is the Retardation factor (Rf), calculated as the distance traveled by the substance divided by the distance traveled by the solvent front. This value is unique for each compound under specific conditions and helps identify unknown substances.

Rf values aren't absolute constants - they're affected by temperature, solvent purity, paper quality, chamber saturation, and even pH. That's why it's important to run known standards alongside your unknown samples. For example, when separating plant pigments, chlorophyll-b might have an Rf value of 0.2, while carotene could be around 0.9.

Common errors in paper chromatography include improper paper positioning, applying too much sample (causing streaking), and contaminating the paper with fingerprints. Always handle chromatography paper by the edges to avoid introducing oils and amino acids from your fingers.

Paper chromatography has numerous practical applications in medicine, forensics, and research. It's used to separate drugs, carbohydrates, vitamins, proteins, and to identify impurities or metabolites in biological samples. While it's advantageous for being simple, rapid, and inexpensive, its limitations include challenges with solvent equilibrium and maintaining stable solvent mixtures.

Looking Forward: While paper chromatography may seem basic, it laid the groundwork for more advanced techniques like HPLC that scientists use today. The fundamental principles you're learning now apply across all chromatographic methods!



We thought you’d never ask...

What is the Knowunity AI companion?

Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.

Where can I download the Knowunity app?

You can download the app in the Google Play Store and in the Apple App Store.

Is Knowunity really free of charge?

That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.

Can't find what you're looking for? Explore other subjects.

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The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

iOS user

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

iOS user

 

Chemistry

40

Dec 10, 2025

4 pages

Understanding Paper Chromatography: Principles and Methods

Paper chromatography is a powerful technique used to separate chemical mixtures based on how quickly their components travel through a medium. This method is particularly valuable for its high selectivity, allowing scientists to separate substances with very similar properties. Understanding... Show more

# PAPER CHROMATOGRAPHY
# CHE 4131 POST LAB

Chromatography

> involves physical separation of the different chemical substances in a mixture

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

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Fundamentals of Paper Chromatography

Ever wonder how scientists can separate the components in a complex mixture like plant pigments? Paper chromatography is the answer! This technique uses filter paper as a solid support and separates components based on their different abilities to travel up the paper.

Paper chromatography works through partition rather than adsorption. The moisture trapped in the cellulose fibers of filter paper acts as the stationary phase, while an organic solvent serves as the mobile phase. The separation depends on factors like molecular structure, size, weight, and polarity of each compound.

There are two main types: paper adsorption chromatography wherepaperimpregnatedwithsilica/aluminaactsastheadsorbentwhere paper impregnated with silica/alumina acts as the adsorbent and paper partition chromatography (where moisture in paper fibers is the stationary phase). This technique is just one of many chromatographic methods, which include thin-layer chromatography (TLC), column chromatography, and high-performance liquid chromatography (HPLC).

Quick Tip: Paper chromatography is one of the most accessible chromatography techniques - that's why it's commonly used in school labs! You can separate complex mixtures with minimal equipment.

!DiagramshowingdifferentpigmentbandsseparatedbychromatographyDiagram showing different pigment bands separated by chromatography

# PAPER CHROMATOGRAPHY
# CHE 4131 POST LAB

Chromatography

> involves physical separation of the different chemical substances in a mixture

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Materials and Sample Application

The paper used in chromatography matters more than you might think! Most experiments use Whatman filter paper, which contains 98-99% cellulose. The choice of paper depends on your sample, solvents, and whether you're doing qualitative or quantitative analysis.

Preparing your sample properly is crucial for good results. Solid samples must be dissolved in a suitable solvent before application. You'll typically apply your sample as a small spot on the "origin line" (the starting point on the paper). In some experiments, you might simply dip the paper directly into a solution containing your sample.

The mobile phase (solvent) choice depends entirely on what you're trying to separate. Scientists often use polar solvents like isopropanol, methanol, or water. If a single solvent doesn't work well, they might create a mixture to achieve better separation. The development happens in a chromatography chamber - usually a glass container that keeps the atmosphere saturated with solvent vapor.

Real-World Connection: The principles of paper chromatography are used in forensic science to analyze ink from crime scene documents. Different inks separate into distinct patterns, helping identify forgeries!

# PAPER CHROMATOGRAPHY
# CHE 4131 POST LAB

Chromatography

> involves physical separation of the different chemical substances in a mixture

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Development Techniques and Visualization

The way you allow your chromatogram to develop can significantly impact your results. In ascending development, the solvent flows upward against gravity (most common in school labs). With descending development, the solvent flows downward, which is faster. There's even two-dimensional development where the paper is developed in one direction, then rotated and developed again - perfect for separating complex mixtures!

After development, the chromatogram needs to be dried with cold or hot air. But how do you see the separated components? If they're colored (like plant pigments), you can see them directly. For colorless substances, special visualization methods are needed. Physical methods include using iodine vapor or UV light, while chemical methods involve spraying reagents that react with specific compounds to produce color.

Scientists can perform both qualitative and quantitative analysis using paper chromatography. For quantitative work, they might compare spot intensity, use photo densitometry (measuring color density), or employ fluorimetry for fluorescent compounds. For particularly sensitive work, radioactive tracers can be used to detect extremely small amounts of material.

Pro Tip: When analyzing amino acids or proteins, ninhydrin spray is commonly used - it reacts with amino acids to produce distinctive purple or brown spots, making invisible compounds visible!

# PAPER CHROMATOGRAPHY
# CHE 4131 POST LAB

Chromatography

> involves physical separation of the different chemical substances in a mixture

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

RF Values and Applications

The most important measurement in paper chromatography is the Retardation factor (Rf), calculated as the distance traveled by the substance divided by the distance traveled by the solvent front. This value is unique for each compound under specific conditions and helps identify unknown substances.

Rf values aren't absolute constants - they're affected by temperature, solvent purity, paper quality, chamber saturation, and even pH. That's why it's important to run known standards alongside your unknown samples. For example, when separating plant pigments, chlorophyll-b might have an Rf value of 0.2, while carotene could be around 0.9.

Common errors in paper chromatography include improper paper positioning, applying too much sample (causing streaking), and contaminating the paper with fingerprints. Always handle chromatography paper by the edges to avoid introducing oils and amino acids from your fingers.

Paper chromatography has numerous practical applications in medicine, forensics, and research. It's used to separate drugs, carbohydrates, vitamins, proteins, and to identify impurities or metabolites in biological samples. While it's advantageous for being simple, rapid, and inexpensive, its limitations include challenges with solvent equilibrium and maintaining stable solvent mixtures.

Looking Forward: While paper chromatography may seem basic, it laid the groundwork for more advanced techniques like HPLC that scientists use today. The fundamental principles you're learning now apply across all chromatographic methods!

We thought you’d never ask...

What is the Knowunity AI companion?

Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.

Where can I download the Knowunity app?

You can download the app in the Google Play Store and in the Apple App Store.

Is Knowunity really free of charge?

That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.

Can't find what you're looking for? Explore other subjects.

Students love us — and so will you.

4.9/5

App Store

4.8/5

Google Play

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

iOS user

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

iOS user