Problem 26 - Chemistry

Question

Why is a burn from steam typically much more severe than a burn from boiling water?

Step-by-Step Solution

Answer

A burn from steam is typically more severe than a burn from boiling water because, even though both have the same temperature of 100°C, steam contains additional latent heat. When steam comes into contact with the skin, it condenses back to water and releases this latent heat, resulting in a larger transfer of heat to the skin and thus causing a more severe burn compared to boiling water alone.

Step 1: Understand temperature differences

Both steam and boiling water are at the same temperature of 100°C. However, the severity of a burn depends not only on the temperature but also on the amount of heat that is transferred to the skin.

Step 2: Explain heat transfer

When an object with a higher temperature comes into contact with an object with a lower temperature, heat is transferred from the hotter object to the cooler one. In the case of steam and boiling water, both are transferring heat to the skin upon contact. The more heat is transferred to the skin, the more severe the burn will be.

Step 3: Discuss latent heat

The key difference between steam and boiling water is that steam contains additional heat in the form of latent heat. When water boils, heat is used to convert water from its liquid state to a gaseous state i.e., steam. This heat that’s used to transition the water into steam, called latent heat, doesn't raise the temperature of the steam, but it is present within the steam.

Step 4: Explain the effect of condensation on latent heat

When steam comes into contact with the skin, it condenses back to water, releasing the latent heat stored within it. This release of latent heat as the steam condenses onto the skin will result in a much larger transfer of heat compared to contact with boiling water alone.

Step 5: Conclude why steam burns are more severe

In conclusion, a steam burn is typically more severe than a burn from boiling water because, although they have the same temperature, steam contains extra heat in the form of latent heat. When steam contacts the skin, it condenses and releases this latent heat, leading to a larger transfer of heat and thus causing more severe burns compared to boiling water.