Minus One Hundred Kilojoules — Per What?

You'll learnthat ΔH is per mole of reaction as written, so total heat scales with amount.

A reaction is handed to you with a number attached: ΔH_rxn = −100 kJ. It reads like a fact about the reaction, the way a melting point is a fact about a substance. It is really a fact about one mole of that reaction, and the heat you actually feel depends on how much of it you run. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · q = n · ΔH_rxn · v5

one number that never moves · one heat that always does

Before you start

What you're looking at

An enthalpy level diagram: reactants on the upper line, products on the lower one, and a bracket measuring the drop.

The question

The label says minus 100 kilojoules. A hundred kilojoules per what?

Step 1 / 12