• Sarah Dann

Chromatography



Happy Sunday all you lovely people!


Who remembers doing this awesome activity at school?


This is a great activity whether you have older ones who can start to understand the concept of chromatography, or if you have little ones who will just be entranced with the pretty colors they can make!


Even my husband joined in and had fun with this one using different patterns and colors!


Fun Fact: Chromatography is a Greek word meaning "color-writing".


What is chromatography?

Chromatography is simply the separation of a mixture, such as the pigments in black ink.


Why is black made up of so many colors?

So as we know the colors of the spectrum are:

  • red

  • orange

  • yellow

  • green

  • blue

  • indigo

  • violet

Each one of these is a different wavelength. When an object absorbs all these wavelengths of visible light, we are left with black, as none or very little color wavelength is reflected.

How this activity works:

This activity works because different molecules are different sizes, such as the different pigments in black ink.

When you have a compound such as non permanent black ink, and you place the ink on a stationary substance, for example, a coffee filter, the color is transferred onto the filter paper. Once water is then introduced, the water travels up the filter paper causing the color to dissolve and molecules to separate. The fact that different molecules are different sizes means, they travel at different speeds. You are then left with a separation of colors, thus leaving you with the colors that have been used to make up the original color you started off with.

This technique is used for many different things ranging from botanical uses to forensic science to food!


What you need:

  • White Coffee Filter Paper

  • Non-Permanent markers/washable felt tip pens

  • Drinking Glass

  • Water

Instructions:

Black is the best color to start this experiment off with, and then move onto using other colors to see what happens.

Using your non permanent markers, draw circles, dashes, dots, or any other design your little one can think of.

Experiment using thick and thin lines, maybe multiple lines too!

Once finished coloring, fold filter into half, then quarters then eighths.


Place just a very small amount of water in the bottom of a glass.

Pop the point (as you can see from the picture, where my thumb is) of your folded coffee filter into the glass of water and watch as the water quickly travels up the filter and disperses the colors.

Some colors will take longer then others, so whilst waiting, start preparing your next coffee filter.


Have fun experimenting with more colors and patterns! Also if you have more then one non permanent black marker, try the other ones too, as you may see a different result!


Have fun folks!


608 views0 comments