Particles in steam, that is, water vapour at 373 K (100°C) have more energy than water at the same temperature. This is because particles in steam have absorbed extra energy in the form of latent heat of vaporisation. When steam tends to cool down, first steam condenses to water on skin and then water tends to cool down to the temperature of the skin. Since steam gives out much more heat than boiling water, it causes more severe burns.