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CChemistryPhysicsS5 to S6Thermodynamics
Lime kiln lab: entropy and free energy
Why must a lime kiln be heated above 800 °C, and why does ice melt only above 0 °C? One equation answers both.
LevelS5 to S6 (and A Level)
TimeAbout 35 min
You useΔG = ΔH − TΔS
PriceFree: no account
🎯 Aim
To investigate how enthalpy, entropy and temperature decide whether a reaction is feasible.
You will learn to
- Predict the sign of ΔS.
- Calculate ΔG at a given temperature.
- Find the temperature at which ΔG = 0.
- Explain why some endothermic reactions are spontaneous.
🧭 What to do
- Choose Lime kiln and move the Temperature until ΔG changes sign.
- Read the temperature where ΔG = 0.
- Try the other reactions and compare their graphs.
- Explain each result with the signs of ΔH and ΔS.
- Answer the questions with the class data.
- Write your conclusion and download your lab report.
📋 The data
ΔH and ΔS of some reactions.
🧠 Investigate: answer from the data
Type your answer and tap Check. Use 💡 Hint first; open the method only when you are stuck.
➕ Get more from this experiment
📝 Free
Print the worksheet (button above), download the data, and save your report. Teachers can project this page in class.
📦 Premium Lab Pack
1 000 RWF
- Worksheet: entropy and free energy calculations with real data
- Thermodynamics problems
- Teacher guide and answer key
- Exam-style questions with marking scheme
👩🏫 For teachers
Use it as a practical when apparatus is missing, as homework, or as a project. Free lesson plans help you plan, teach and assess.
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