A spirit burner is simply a method of burning alcohol or other spirits in a relatively safe fashion. Like a candle, a spirit burner uses a wick to maintain a flame to vaporise and burn fuel. Simple spirit burners are easy to make in chemistry class and have many advantages. The wick itself can be long-lasting, and most burners are easy to refuel, so one burner can last a long time.
Make a hole in the middle of the metal lid using the corkscrew. Widen this hole far enough for the string to pass through without falling back. The string will act as a wick for the spirit burner, so it is essential that it stays in place. Make four smaller holes midway between the centre and rim of the lid. These prevent a vacuum forming in the jar as the fuel is burnt. If you haven't already done so, pass approximately 1,3 cm (1/2 inch) of the string through the central hole, to act as the wick.
Fill the jar with the cotton wool. Make sure that the wool is not packed so tightly into the jar that no liquid can be poured in. The cotton wool will absorb most of the fuel and acts as a slow-release system, so the wick does not get over-soaked and burn too quickly.
Fill the jar with the methylated spirits. Be careful not to overfill the jar as there needs to be room for the string as well as the liquid and cotton wool. Screw the lid onto the jar. Leave for five minutes so the wick absorbs some of the fuel. The spirit burner is now ready to be used and will continue to burn as long as there is fuel feeding into the wick.
Different kinds of wick can be used in place of the string. Some burn faster, some slower, so experiment to find the type of wick that suits your needs best. Similarly, different kinds of spirits can be used in place of meths. Ethanol and propanol are excellent alternatives so, again, experiment to see which best suits you. Using a clear glass jar makes it easier to see when you are running low on fuel.
As with all things in chemistry class, care and attention are needed when handling chemicals. The spirits in a spirit burner are highly flammable, so if spillages happen, wash the area thoroughly. Spirit burners can get very hot when in use, especially the metal lid. Always be sure to let the burner cool before touching it, or use heat-proof gloves if this is not possible.