identifyinfg substances

carbon dioxide

Use a balloon of CO2 to gather gas into two boiling tubes. Take out the pluck on one boiling tube pour in 1cm of limewater and shake. The other tube do the same thing but pour bicarbonate indicator.

Oxygen

fill a boiling tube of oxygen from the balloon by displacement of water. Light a splint then blow it out but leave it glowing red. Unscrew the top of the boiling tube and put it in the splint

hydrogen

Put 2cm of dilute hydrogen acid into a test tube. Add a magnesium strip into the acid to generate hydrogen. While it is bubbling put a lit splint into it. Place your thumb over the end and allow gas to build up. Put a lit splint in and listen.

water