HOME＞Experiments＞For Kitchen＞EH004 Black Snake
When combined, sugar and baking soda create a rather ominous-looking black snake.
This experiment should be conducted with a guardian, in an outdoor location where open flames can be safely handled, such as a campsite or barbecue area. Please exercise extreme caution when handling the fuel.
Requires
equipments
・heat-resistant container (e.g. Pyrex)
・lighter
reagents
・baking soda
・sugar
・Paraffin oil (though ethanol can also be used, paraffin oil is safer)
・sand
Methods
1.
Mix 10 g of sugar and 5 g of baking soda together.
2.
Spread sand evenly in a heat-resistant container and soak it with paraffin oil.
3.
Place the powder mixture from step 1 in the center of the sand, then ignite the paraffin oil.
Clearing
Place the sand and the black snake in a plastic bag. Since there may be paraffin oil accumulated or attached to the bottom of the heat-resistant dish, wipe it off with paper towels and place the used towels in the same plastic bag. For added safety, it’s recommended to double-bag the materials. These can be disposed of as combustible waste.
Ideally, the heat-resistant dish should be disposed of as waste. However, if it has other uses, make sure to thoroughly wash it with dish soap or a similar cleaning agent after wiping off the paraffin oil.
If there is any excess paraffin oil, you can store it with an oil lantern, which could be useful in case of an emergency. If you need to dispose of it, please follow the disposal guidelines provided by your local municipality.
Principle
Baking soda (sodium bicarbonate) undergoes thermal decomposition when heated.
2NaHCO3 → Na2CO3 + CO2 + H2O
The carbon dioxide gas released during this process causes the heated, melted sugar to expand. It’s similar to the way soap creates a foam layer when bubbled through a straw. As the sugar expands, it continues to heat up and eventually turns into carbon. Unlike the liquid sugar, this carbon has no flowability, so it retains its shape and forms the solid black “snake” structure.
As the melted sugar is pushed upward by the carbon dioxide, the process of carbonization continues. With each cycle of heating and expansion, the sugar keeps turning into carbon and stretching out. This repetitive process causes the carbonized sugar to elongate, eventually forming the characteristic “snake” shape.
If you substitute the chemicals with mercury thiocyanate, you can create a different-colored snake, known as the “Pharaoh’s Snake.” This experiment is often shown on YouTube. However, since it involves the use of mercury, it is extremely hazardous and should not be performed in practice due to the toxicity and risks associated with mercury. It’s understandable to feel disappointed about not being able to conduct such an experiment, but safety should always come first.