Thermochemistry

by Dean J. Campbell* *Bradley University, Peoria, Illinois

I have always been fascinated by chemical reactions that form shiny, metallic mirrors.

A year ago I stumbled across a fun way to present the reaction between calcium metal and water. Check it out (including a video explanation): The Devil's Milkshake. Ca(s) + H₂O(l) → CaO(s) + H₂(g)       Equation 1

Prologue: The application of Hess's Law frequently presents students with conceptual problems, and I believe that performing a series of experiments that confirms Hess's Law, is probably the best way to impart a robust understanding of this principle. A plaque on the wall of the Oxford University Biochemistry Department reads: