Chemical Reactions

Chemical Reactions

Year 7 dedicated the first week of the new term to learning how to perform investigations in Chemistry.

They measured variables, drew apparatus using scientific drawings and identified hazards; but the highlight of the week was when they learnt to test for gases.

During chemical reactions gases are often formed but as many of these are colourless it is often impossible to identify them by sight alone. Year 7 however discovered that we can perform certain tests to find out which gas has been formed.

During one experiment the boys put a glowing splint into the test tube which then burst into flames. They learnt that this reaction is an  indicator that the gas inside was Oxygen, which, they also learnt, is highly flammable!

In another experiment the boys blew into clear Limewater which turned milky (chalky). They learnt that this result demonstrates that they are breathing out Carbon Dioxide.

Later in the term, when the children learn about acids and alkalis, we will also learn how to test for hydrogen. This test will also involve a glowing splint. What do you think will happen when the splint makes contact with the Hydrogen gas?

Hendon Prep School