This is the CHaOS demonstrator website, mainly intended for our student volunteers. Click here if you were looking for our main front page.

CHaOS Experiment Explanations

CHaOS has a large collection of different experiments that we use at our events,as listed below. The links take you to experiment explanations aimed at explaining experiments to new CHaOS demonstrators (typically Cambridge science students), as well as risk assessments.

You can filter experiments by subject. There is significant overlap between subjects, many engineering experiments could easily be classified as physics, medical experiments as biology...

Title Intro Subject
** How to Float ** Keeping demonstrators happy. Other
2020 CBS talk - sight unseen Other
A Bug's Life All sorts of creepy crawlies preserved in perspex blocks or jars. Biology
Air Rockets Launching lemonade bottle air rockets along a rope Physics
Animal Cognition A challenge to get people thinking about animal intelligence Biology
Anti-bubbles Make fascinating bubbles which rather than floating on water actually sink. Physics
Arch Bridge Building an arch bridge, and then walking over it. Engineering
Articulated Knee Model and Tendon Hammer A spare plastic skeleton leg, now with added ligaments. Medicine
Blood Glucose Medicine
Blood Groups Why are blood groups important? Medicine
Bouncing Balls and Falling Toast Looking at odd properties of bodies with spin. Physics
Brain Model ft. Pipecleaner Neurons Anatomical model of the brain and making model neurons from coloured pipe cleaners! Medicine
Bubble Guns Bubbles Physics
Build a Tree Talk about the different parts of a tree whilst building one out of craft materials Biology
Camera obscura and lenses Peering at the outside world through a lens. Physics
Cantilever Bridges Building a series of cantilever bridges Engineering
Carbon Allotropes and Molecular models Chemistry
Cathedral How can we use arches to hold up a cathedral? Engineering
CBS Journey to the centre of the Earth Geology
CBS Robotics Workshop Robotics Workshop run during CBS, in conjunction with Robogals Cambridge Engineering
Chromatin Pipecleaner Models Explore the world of epigenetics, using pipecleaners and corks to model DNA and the chemical changes done to it to turn genes on and off. Biology
Cleaning Coppers Removing copper oxides from coins. Chemistry
Cloud Formation in a Bottle Demonstrate cloud formation as air pressure drops. Physics
Colour Mixing and Spectra Dimmable, focussed red, green and blue lamps for experimenting with light colour mixing Physics
Creepy Crawlies Looking at a variety of small creatures that you can find in your garden Biology
Dissecting sheep's eyeballs Dissecting a sheep's eyeball to show the structure of the eye Medicine
Drosophila This experiment aims to introduce kids to a wonderful model organism, the Drosophila fruit fly. Biology
Ear model Anatomical model of the ear, with removable parts. Medicine
Ear switching hat This magical hat will confuse your senses! Medicine
Electrolysis Splitting water into hydrogen and oxygen, and using the recombination of these to launch ping-pong balls. Chemistry
Electromagnetism Making electricity, and using it to spin a motor. Physics
Emperors, Spies and Seaweed: writing messages only you can read Computer Science
Engines What are the different types of engine, and how do they work? Engineering
Exercise and Heart rate, Stethoscopes and Heart Model When you exercise your heart beats faster! Medicine
Exploring genes Props to explain DNA and molecular biology, including a plastic DNA gel! Biology
Eye Model and Blind Spot Test Anatomical model of an eye with removable parts to show the structures inside. Medicine
Fire Extinguishers Demonstrating the power of a carbon dioxide fire extinguisher. Chemistry
Fruit Batteries and fuel cell construction Chemistry
Giant Bubbles Making giant soap bubbles and looking at how they behave in different shaped frames. Chemistry
Giant intestine model Functional model of the intestine Medicine
Graph Theory Find out about the mathematics of Graphs. Maths
Hand Model Large working model of a hand and forearm, with all the tendons to show how a hand works. Medicine
Handy Engineering Build a small working model hand from card and straws! Medicine
Hexaflexagons Groups, symmetries and hexaflexagons Maths
Horse Racing Probabilities of rolling dice. Maths
Hot Air Balloons Making hot air balloons with plastic bags and a toaster. Physics
Jaw Model and Giant Teeth Anatomical model of the half jaw, parts can be removed to show structure of the teeth. Medicine
Kiwi DNA Breaking open cells of a kiwi fruit and making the DNA inside visible to the human eye Biology
Kruskal's count Players follow playing cards around a circle and watch as they magically come together Maths
Larynx model Functional model of the larynx Medicine
Leaning Tower of Lire Balancing blocks on the edge Engineering
Lenz's Law What happens when we drop a magnet through a pipe? Physics
Life Cycles Perpex blocks with specimens of frogs and bees from different lifecycle stages. Biology
Locusts and Glowsticks Using glow sticks to talk about chemical kinetics. Chemistry
Loops, Bumps and Dives: The Physics of Rollercoaster Rides Physics
Lung Model Working model of the lungs with diaphragm and rib cage. Medicine
Mechanical advantage Using pulleys and levers to explore mechanical advantage Engineering
Microbes (bacteria, viruses and parasites) Three boxes of kit to explain microbiology Biology
Microscopes & Cells Examining a variety of objects under a microscope, including a variety of slides Biology
Mini Explosions Exploding film canisters with lemon juice and bicarb. Chemistry
Mini-beasts A variety of sea life and freshwater animals observed using microscopes Biology
Miscibility (Sugar Rainbows) Chemistry
Monty Hall's Perplexing Goat A wonderful experiment of probability involving a cuddly goat called Bertrand, a couple of coins, three doors, and three boxes. Maths
Mould Effect (Self-Siphoning Beads) Letting a chain pull itself out of a beaker under its own gravity Physics
Near IR webcam Use a modified webcam to see into the near infrared. Physics
Non-Transitive Games What's the best option in games of chance? Maths
Oil and Pyrex Using the refractive index of vegetable oil to make a glass bowl 'disappear'. Physics
Optical Illusions Display of several optical illusions, to illustrate the way the brain perceives certain visual stimuli Medicine
Organ Vest A velcro apron with detachable 3D organs, to show what's inside your body. Medicine
Peak flow Using a peak flow meter to measure peak flow rates Medicine
Phase Game Game introducing the phases of matter and phase changes Physics
Plant evolution & pollinator game Plant evolution timeline and matching plants with their pollinators Biology
Plants Plants - looking at germination, their structure and how they produce energy by photosynthesis Biology
Platonic Solids Explore the five platonic solids and other 3D shapes. Maths
Polio, vaccination and disease eradication Use our cuddly poliovirus to learn how we can prevent and eradicate diseases! Biology
Pond Life A selection of organisms from a local pond or rock pool Biology
Prism Goggles Demonstrate how the brain adapts to changes in environmental input using prism goggles. Medicine
Projective Dobble The maths of Dobble Maths
Psychedelic Milk See the amazing patterns made by food colouring and detergent in milk. Chemistry
Random Walks Choosing direction using a coin flip. Maths
Recipes from a Star Recipes from a Star: From Puzzling Planets to Black Holes Bizarre Physics
Red cabbage Making a natural pH indicator. Chemistry
Relative Senses A variety of experiments to show how our senses are relative rather than absolute: Medicine
Renewable Energy: Uses of Electromagnetism Making power using wind and water! Physics
Resonance What is the link between earthquakes and cello strings? Physics
Reversible Flow Turn syrup one way, then the other, and see that it gets back where it started. Physics
Rod Climbing A polyacrylamide solution, which "climbs up" a rod when it is rotated in the solution Chemistry
Scale of the Solar System By comparing sizes and distances we can scale our solar system all the way up from the Earth and the Moon, up to our nearest star, and you might be surprised how far that actually is! Physics
Seeing Sound Use an oscilloscope and slinky spring to see how sound travels Physics
Skeleton and bones Meet Boris, the friendly CHaOS skeleton. Medicine
Slug Bubbles Does a tube of water drain more slowly with a bung in the top? Physics
Sodium Acetate Rapid crystal growth from sodium acetate. Chemistry
Sounds from an oven shelf Get very strange sounds from an oven shelf. Physics
Spaghetti Loading Materials Science
Spinning Eggs How to test if an egg is uncooked or hard boiled. Physics
Spinny Chair Use a freely spinning chair, some masses and a bicycle wheel to see some unintuitive physics. Physics
Sunset Model Why is the sky blue and the sunset red? Physics
Surface Tension Exploring surface tension through floating paperclips and racing boats Physics
Suspension Bridge A suspension bridge made from rope and wood that children can walk across. Engineering
Sweet Chromatography Using chromatography to investigate the colour of food. Chemistry
Taking pictures as a vet: How to see inside your pet - CBS 2019 talk Biology
The Mathematical Bridge How can a bridge stay up without bolts? Engineering
Thixotropic sand and fluidised bed Looking at floating and sinking using a bed of sand Chemistry
Trebuchets Using a medieval inspired siege-weapon to launch bean bag bunnies Engineering
Tree Biology
Turtle Robots These turtles want to draw you shapes. Computer Science
Urinalysis Medicine
UV (Fluorescence) Looking at how materials fluoresce in UV light. Physics
Vacuum Bazooka Firing a projectile using a vacuum cleaner and a long tube. Physics
Vacuums Various demonstrations using a vacuum pump. Physics
Vortices Make smoke rings and see how they form Physics
Water Fibre Optics Constraining light in a stream of water, making it work like an optical fibre. Physics
Water rockets Launching lemonade bottle water rockets with a foot pump. Physics
X-Rays A collection of X-rays and other forms of medical diagnostic imagery. Medicine
Xylem Showing one of the transport systems in plants. Biology
Yeast & bread making The idea is to look at how yeast grows and how it relates to bread making. It involves getting the kids to make bread dough. Biology