Thermochemistry

The conversion of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) is an extremely important energy source for living organisms. Under common physiological conditions, it can be expressed as:

The December 2024 APTeach presentation explored common misconceptions and student stumbles in Thermodynamics. View the video summary and the presentation slidedeck.

The purpose of this article is to show you how to present Hess’s Law in a logical manner, with essentially no reliance on memorizing.¹ Students will understand that the different ways of calculating ΔH_r using Hess’s Law are ALL THE SAME.

The “Pharaoh’s Serpent” chemical reaction involves the thermal decomposition of mercury (II) thiocyanate:^1,2

This activity is intended for Chemistry Teachers who plan to discuss the energetics of phase changes.

Co-Authored by Rhiannon Davids* and Dean J. Campbell* *Bradley University, Peoria, Illinois

An experiment that has always fascinated me is observing what happens when CO₂ is bubbled into limewater (which is a saturated solution of calcium hydroxide).^1-2 This experiment can be carried out by blowing bubbles of exhaled breath (which contains roughly 4% CO₂)³ through a straw into limewater.