Potassium chlorate decomposes into potassium chloride and oxygen gas, which means that when the glowing splint is inserted into the test tube, the flame will have enough fuel to fully reignite the splint. When the manganese dioxide is added, this will increase the rate of the production of oxygen in the reaction, without affecting the state of the manganese oxide.
2cm of potassium chlorate (on scoopula)
A pinch of manganese dioxide
The 2 centimetres of potassium chlorate was inserted into a test tube, which was then placed at a slight angle onto the retort stand. The Bunsen burner was then lit using the flint sparker, and the flame was placed underneath the test tube to heat up its contents. Once a noticeable reaction had began to occur (the potassium chlorate melting), a glowing splint was inserted into the test tube to test for the gas created by the reaction. After the glowing splint was removed and the reaction had fully stopped, the heat source (i.e. Bunsen burner) was removed and the pinch of manganese dioxide was added to the test tube. A glowing splint was then again inserted into the test tube to identify the gas being produced.
Upon placing the flame underneath the test tube, no reaction occurred immediately. However after the substance was given several seconds to increase in temperature, it began to appear as if it was melting. This was the decomposition reaction via heat of the potassium chlorate occurring. Upon this observation, the glowing splint was inserted into the test tube. When the splint came in contact with the cloudy gas that was being produced by the reaction, the flame erupted brightly, which proved that the gas being produced was oxygen. After this observation was made, the flame was then removed and a small pinch of the black, powdery substance manganese dioxide was added to the content