Ever wondered why icebergs fizz? Or why the sky is blue? Or how a worm's heart works?

Each month we dig out the finest nuggets of trivia related to this year’s National Science & Engineering Week theme. Whether you’re feeding your curiosity or finding inspiration for activities, we hope you enjoy reading this month’s “did you know…?” bulletin. 

This month...
gunpowder, treason and plot

The Chinese had perfected the use of gunpowder over 650 years before Guy Fawkes’ infamous plot to blow up the king of England was discovered in 1605. The earliest known written recipe for gunpowder dates from 1044. It details a powder that was later used in bombs, incendiaries, projectiles and fireworks.

Gunpowder is made up of potassium nitrate, charcoal and sulphur. When gunpowder combusts, the chemicals in gunpowder react, releasing large amounts of heat and gas.
The rapidly generated heat from the combustion of gunpowder causes the gasses to expand very quickly. It is this expansion of gasses that we think of as an explosion. The potassium nitrate in gunpowder contains the oxygen required for the combustion reaction to take place so gunpowder can explode even where there is no air.