Molecules at Home

Detective needed: molecules wanted! Chemical substances are hiding in plain sight in our houses: can you help us find them?

To complete this task, you will need to fill in an identikit for them, by using our database of crystal structures, called the Cambridge Structural Database (CSD).

From the crystal structures you will learn about our “runaway” molecules and this will help you find where they might be hiding! You can also find this activity on the Festival Zine at page 30.

Get your detective hat ready and let’s find some molecules!

What Do You Need?

  • A phone with a QR scanner or a computer, tablet or phone so you can click on the web links.
  • Print out of the three “Wanted” posters known as identikits that you can find on this page or if you don’t have a print out then a piece of paper to reproduce them.
  • Pen or pencil and if you have them coloured pencils to draw the different coloured atoms.

Health and Safety

The activities on this page are carried out at your own risk and children should be supervised by an adult. Please read these health and safety guidelines to reduce risks.

  • Children should not be left unsupervised with any small items that could be harmful to ingest.
  • Any access to the internet from minors should be done under adult supervision.
  • If you print and cut out the indentikits please be aware of potential cuts from scissors or papers.


  1. To start your search of the wanted molecules, ask an adult to click the link or scan a QR code on the “Wanted” poster with a phone. This will bring you to our database, the CSD, where you can find information about the chemical structure.
  2. Now, to fill in the “Wanted” poster, known as an identikit, you need to find the common name of the substance, and then draw the molecule that you can see. In the database we use grey for carbon atoms, red for oxygens and white for hydrogens.
  3. Where can you find the molecule in your home? Use the information from the CSD to help you fill in where the runaway molecule was last seen (write or draw it). Hint: the images below provide some clues. 
  4. Repeat the search for each of the chemicals by clicking on the links or scanning the QR codes, filling in the identikit for each.


Once you find all the molecules:

  1. What do they have in common?
  2. What differences do you observe?
  3. Did you notice that there are only three different elements (C, H, O)?

Download your 3 identikits below

Additional Resources

  • Scanning the QR codes leads you to these pages: EQOPAD,  JEMSAW,  SUCROS01. Note that EQOPAD and JEMSAW have multiple entries in the database, you can explore the various entries by clicking on each one.
  • Familiarise yourself with the 3D viewer on our website.