Introduction:
Burns can occur from various sources, including heat, chemicals, electricity, and radiation. When it comes to burns caused by heat, both boiling water and steam can cause severe injuries. However, the severity of the burn depends on several factors, including the temperature, exposure time, and the individual's sensitivity.

Boiling water:
Boiling water has a temperature of 100 degrees Celsius (212 degrees Fahrenheit). When it comes into contact with the skin, it can cause thermal burns. The severity of the burn depends on factors such as the temperature of the water, the duration of contact, and the surface area affected.

Steam:
Steam is formed when water reaches its boiling point and evaporates. It is essentially water vapor and can cause burns due to its high temperature. Steam can be hotter than boiling water because it carries more thermal energy. The temperature of steam can range from 100 degrees Celsius (212 degrees Fahrenheit) to several hundred degrees Celsius (over 500 degrees Fahrenheit), depending on the pressure and source.

Comparison:
Both boiling water and steam can cause severe burns, but steam generally has the potential to cause more severe injuries. Here's why:

1. Heat transfer:
When boiling water comes into contact with the skin, it transfers heat to the skin through conduction. However, steam transfers heat through both conduction and condensation. This means that steam releases its latent heat of vaporization when it comes into contact with a cooler surface, such as the skin. As a result, steam can deliver more thermal energy to the skin compared to boiling water alone.

2. Penetration:
Steam has the ability to penetrate deeper into the skin compared to boiling water. Due to its gaseous nature, steam can access areas that liquid water cannot reach easily. This deeper penetration can result in more extensive damage to tissues.

3. Heat retention:
Steam has a higher heat retention capability compared to boiling water. When steam condenses on the skin, it releases a large amount of heat, which can further contribute to the severity of the burn. This heat retention prolongs the exposure to high temperatures, leading to more tissue damage.

4. Vaporization:
Steam can cause burns not only due to its high temperature but also due to the phase transition from a gas to a liquid. When steam condenses on the skin, it releases energy in the form of latent heat of vaporization. This energy can cause additional damage to the skin and underlying tissues.

Conclusion:
In summary, while both boiling water and steam can cause severe burns, steam generally has the potential to cause more extensive injuries. The heat transfer, ability to penetrate deeper into the skin, heat retention, and the energy released during vaporization contribute to the increased severity of steam burns. It is crucial to exercise caution and take appropriate safety measures when dealing with both boiling water and steam to prevent burns and minimize the risk of injury.

We know that to convert water from liquid to vapour state , it is required to supply latent heat of vaporisation . This means that water at 100 degree celsius gets converted into vapour state only if latent heat ( or also known as hidden heat ) is supplied to it . When the boiling water at 100 degree celsius gets converted into steam , it has more heat than water at 100 degree celsius ( in the form of latent heat ) . So when steam falls on our hand , it condenses to form water and it gives out latent heat of vaporisation ( whose value is 22.5 × 10^5 J/kg ) . Water at 100 degree celsius does not have any latent heat . Therefore steam produces more severe burns than water .