Entropy, Free Energy & Reaction Feasibility — Drills · Grade 11 Science
Chapter: Chemical Energy & ThermodynamicsWhat these drills covers
By the end of Entropy, Free Energy & Reaction Feasibility you should be able to:
- I can calculate ΔG with consistent energy units and kelvin temperature.
- I can distinguish thermodynamic favorability from reaction speed.
2 questions, numeric and written answer, each with a worked explanation.
Vocabulary used: entropy, Gibbs free energy, spontaneous.
Problem 1
ΔH=−50kJ/mol, ΔS=−.100kJ/mol·K, T=300 K. Find ΔG.
Hints
Write the relationship first; substitute with consistent units.
Answer and explanation
-20 kJ/mol
−50−300(−.100)=−20.
Problem 2
Can a favorable reaction be slow?
Answer and explanation
Yes. A high activation-energy barrier can limit its rate.
Response criteria
- State a scientifically accurate conclusion.
- Show the calculation or mechanism that supports it.
- Include units, conditions, or limits where relevant.