Growing Sugar Monster

Grow an amazing sugar monster from common kitchen ingredients! 

What you need:

1 cup icing sugar
1/4 cup bicarbonate soda
99% isopropyl alcohol or lighter fluid (>60% will also work, but will not be as effective). WARNING - this is a flammable liquid and requires adult supervision
Matches (preferably long)
Heat-proof dish and mat
Safety glasses and heat-proof gloves

What to do:

WARNING - This activity requires adult supervision as it uses a flammable liquid and matches. 
Add the icing sugar and bicarb soda together and mix well.
Find a clear space in a well-ventilated area away from smoke detector to place heat-proof dish on the mat, and pour in sand to create a mound. Create a well in the centre of the sand.
Carefully pour the alcohol over the sand (mostly in the centre, in and around the well).
Spoon the icing sugar and bicarb into the well.
Ensure the alcohol bottle is closed and has been moved well away before using a match to ignite the alcohol on the sand.
The sugar mixture will slowly start to form a black 'monster'.
The dish will be extremely hot, so do not attempt to move it without heat-proof gloves.
When the experiment has cooled, it can be put directly into the bin.

Why is it so?

The heat from the alcohol burning leads to a combustion reaction with the sugar, producing water vapour, carbon dioxide gas. However, because the sugar in the middle does not have access to oxygen, combustion cannot occur here. This sugar undergoes thermal decomposition, which separates it into carbon and water vapour. The bicarbonate soda also undergoes thermal decomposition, and produces carbon dioxide. These form bubbles in the carbon, creating the 'tower' and is why it feels soft (be careful to let it cool before you touch it!).