Why is it generally more severe to be burnt by steam at 100°C than by boiling water at 100°C?
Steam contains more latent heat of vaporization.
Both steam and boiling water at 100°C are at the same temperature, so steam is not hotter than the boiling water.
However, when steam at 100°C condenses on the skin, it releases its latent heat of vaporisation (\(\approx 2{,}260 \text{ J/g}\)) in addition to the heat lost when the resulting water cools from 100°C to body temperature.
So the total heat delivered to the skin per gram of steam is roughly:
\(Q_{steam} = m \cdot L_v + m \cdot c \cdot \Delta T\)
whereas for boiling water it is only \(Q_{water} = m \cdot c \cdot \Delta T\). The extra latent heat makes steam burns much more severe.
Hence the correct answer is option 2).
Important Questions from Heat and Transfer
The brightness of a star depends on its
Thermocouple is a device which converts
To change a temperature on the Kelvin scale to the Celsius scale, you have to ________ the given temperature.
Ramu mixes 2 litres of water at 100°C and 18 litres of water at 32°C. What temperature will the water have after mixing?
Which one of the following is the correct relation between the Kelvin temperature (T) and the Celsius temperature (tc)?
