We have all heard of Oxygen but never seen it; ‘cause you can’t see it. It is a colourless gas and as such invisible as air. There are different ways to make a sample of this gas.
Method 1 Adult supervision Essential
You need. Can be purchased from a Pharmacy. A substitute such as from a fused bulb or even a fish tin may be used. Can be improvised by splitting a piece of wood. A tin may be kept on a hot plate.
Method.
Add about a teaspoon of dark purple condys crystals into a hard glass test tube.
Theory:-
Potassium permanganate → Potassium manganate + Manganese dioxide + Oxygen.
2KMnO4 → K2MnO4 + MnO2 + O2
 How do we know that the gas is Oxygen?
Test for Oxygen The usual test for Oxygen is the glowing splint test. When you expose a glowing red splint into the gas , it will start burning with a flame.
Method 2. You need:- (From a pharmacy or a beauty saloon)
Theory: 
Hydrogen peroxide is an unstable compound. Oxygen is bound to water very loosely. So it can decompose as indicated here. H2O2 = H2O + O2 When this solution is used on wounds oxygen bubbles fizzed out. It is due to an enzyme catalase present in blood. There are many substances that catalyze this reaction. In labs they use a black powder called Manganese dioxide. This substance is present in torch cells mixed with carbon.
For this experiment we suggest the use use of Live yeast.
Method:- 
Add a few ml. of Hydrogen peroxide solution into the bottle. Then add the live yeast slowly and watch what happens. You will soon realise that a gas has been released. If it is Oxygen it will catch fire. Physical Properties of Oxygen Colour……….Colourless Odour……….No smell Weight………16 times heavy as Hydrogen Solubility …….. Slightly soluble | 
Fig. Passing Carbon dioxide through lime water.