📖 Theory▼

Aim: To measure the energy released when different alcohols burn and compare them.

Method: A measured mass of alcohol heats 100 mL of water; energy to the water Q = mcΔT (c = 4.2 J g⁻¹ °C⁻¹).

Homologous series: methanol → ethanol → propan-1-ol → butan-1-ol add one –CH₂– each. Each extra carbon means more C–C and C–H bonds to burn, releasing more energy per mole.

⚠️ Safety▼

• Alcohols are highly flammable — keep bottles stoppered and away from the flame; never refill a burner that is lit or hot.

• Methanol is toxic and can burn with an almost invisible flame — handle with extra care and good ventilation.

• The metal can and water get hot — use a heat-proof mat and let apparatus cool before touching.

• Cap the spirit burner to extinguish it (do not blow it out); tie back hair and loose clothing.

• Wear goggles; combustion produces carbon dioxide (and some carbon monoxide/soot if incomplete) — work in a ventilated area.

Select Alcohol

🔮 Predict before you burn

Predict the trend across the series before running the experiment.

Procedure

100 mL water Metal can Methanol Spirit Burner Initial mass: — | Final mass: — Temp: 25°C Energy: —
Observations
Follow the steps...

Comparison Table

AlcoholΔTEnergy/g
No data