Two Terms, One Verdict

You'll learnhow to combine ΔH and ΔS into ΔG, why the sign of ΔG is the whole answer, and how temperature can flip it.

A reaction gives out 40 kilojoules of heat. That sounds like the end of the argument and it is only half of it, because a second term can pull the other way — and when the two disagree, the temperature settles it. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · ΔG = ΔH − TΔS · WATCH THE J / kJ · v2

ΔH and TΔS, and what happens when they disagree

Before you start

What you're looking at

Signed bars measured from a zero line, with anything pointing left counting as favourable.

The question

Both reactions here release heat. Why is only one of them favoured?

Step 1 / 12