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Why Steam Burns Worse Than Boiling Water
📖 Why Steam Burns Worse Than Boiling Water
Here's a painful truth: getting scalded by steam at 100°C causes FAR worse burns than boiling water at 100°C. Same temperature — so why the difference? Because steam carries "hidden" energy — the energy that was needed to turn water into steam. When steam touches your skin and condenses back to water, all that hidden energy DUMPS into you. The word "latent" literally means "hidden" — it's energy stored in the state change itself, invisible to thermometers!
Specific Latent Heat Equation (ON FORMULA SHEET)
E = m × L
Energy (J) = mass (kg) × specific latent heat (J/kg)
Understanding Specific Latent Heat
Specific latent heat (L) is the energy needed to change the state of 1 kg of a substance WITHOUT changing its temperature. The word "specific" means "per kilogram."
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🧠 Memory Aid
Remembering the two types:
- Fusion = Freezing/melting (solid-liquid boundary) — think "F for Floor" (the lower level)
- Vaporisation = Very hot (liquid-gas boundary) — think "V for Very high energy"
The equation E = mL: Think "Enormous mass x Latent heat = Enormous energy." Or use the triangle: E on top, m bottom-left, L bottom-right. Cover what you want to find.
Why steam burns more: Steam at 100°C → skin → condenses → releases 2,260,000 J/kg (latent heat) PLUS cools down further. Boiling water only cools down — no latent heat released. So steam is the nastier one.
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Quiz · Question 1 of 13
What is specific latent heat?
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This topic in real past papers
Every real exam question we've found on specific latent heat, with a full worked answer.