Could someone please tell me briefly how lethal gas works? Thanks! kenny

The condemned person is strapped into a chair within an airtight chamber, which is then sealed. The executioner activates a mechanism which drops potassium cyanide (or sodium cyanide) pellets into a bath of sulfuric acid beneath the chair; the ensuing chemical reaction generates lethal hydrogen cyanide gas.

Explanation:

Hope that helps! :)

When the fluid cools, the kinetic energy of the molecules decreases. This causes the molecules to slow down and move closer together. Since the molecules are closer together, the density of the fluid increases and the fluid sinks.