will introduce the two major types of chemical reactions, polymer
chemistry and the importance of plastics in everyday life.
reactions can be classified by whether they produce or absorb
heat. Reactions that produce heat are called exothermic. They
are quite common. Combustion or burning is an exothermic reaction.
second type of reaction, called endothermic, absorbs heat from
its surroundings. The reaction that produces slime is endothermic.
It absorbs the heat from your hands as we handle it, which is
why the slime feels cold and clammy to the touch.
slime is a special kind of substance called a polymer. Polymers
are more commonly known as plastics and are found practically
everywhere in everyday life. For example, we use shopping bags,
saran wrap and Tupperware, drive cars on rubber tires, and wear
polyester, nylon and rayon fabrics. Polymers are substances
made of repeating chemical units linked together like a chain
to form a long molecule.
example, the ethene molecule becomes the repeating
chemical unit when it is linked to other ethene molecule to
form a polymer called polyethene.
What You Need
glue (Elmer's school glue is best)
medium-sized plastic containers
What To Do
125 ml water with 125 ml glue in one container.
the food colouring.
another container, mix 250 ml water with 45 ml borax.
60 ml of the borax solution to the glue solution and mix it
with your fingers.
the mixture around with your hands until it thickens.
Then put it on a table and knead it with your hands until
there is no obvious liquid on the surface of the slime.
and squish the slime to observe how it behaves. Is it
a solid or a liquid? Does it feel warm or cold?
It should feel cold, especially when it's stretched very
thinly. How thin can you stretch the slime before it
breaks? Does it stretch better when you pull on it quickly
or when you pull on it slowly?
slime in a resealable bag and keep it in a cool place.
the reaction needs heat, so the more the slime is handled,
the harder it gets.
NOTE: The quantity of the two component solutions can be increased.
Maintain the 1:1 ratio for the water and the glue mixture. For
the Borax solution, add approximately three tablespoons of Borax
per cup of water.