Title says all. How does vapor from e-cigs not burn you when steam from boiling water can cause blistering?
In: Physics
It’s apparently pretty [complex chemistry](https://www.reddit.com/r/askscience/comments/2l8e7k/comment/clsi9ej). Steam is high temperature water to the point it has become a gas, while vapor is at a lower temp and is still in the form of water droplets floating in the air.
The droplets are small enough that they cool very rapidly, since they have a large surface area and not much volume of liquid inside they can not only cool by dissipating heat, but they also vaporize, and that sucks even more heat away
It’s kind of like how clouds or fog doesn’t burn you either. You can get vaporised liquid that doesn’t stay hot forever.
Interestingly, the ‘steam’ you see is not actually water vapour; it instead is made of many small water droplets suspended in the air. Water vapour is not visible to the human eye.
Interesting question.
While I’m not sure, I guess it could be because of the difference in the rate of heat transfer. You begin to feel burning when the temperature of liquid/gas is above 45 degrees Celcius. My guess is that for the case of vaporized liquids the heat transfers quickly to the surrounding after they are formed. When vaporized liquids lose heat (energy), they transformed back into the liquid phase (ie. tiny droplets). These droplets carry insufficient amount of heat (energy) to make your skin feel burnt.
For the case of steam, I guess that the heat transfer occurs at a slower rate. Water droplets are still formed as the temperature of the water vapor is lower than 100 degrees Celcius. But the temperature of these droplets is still higher than 45 degrees Celcius, making you feel burnt when they land on your skin.
The difference in the rate of heat transfer could be dependent on the materials (water, oils, fragrances, etc.), the size of droplets (surface area and volume), and the temperature in the surrounding environment. The last factor is important in the case of e-cigs and boiling water. Usually, the temperature of the surrounding of ecigs is around 25 C while that of boiling water is higher than 25C. A higher temperature difference leads to a higher rate of heat transfer, making the heat transfer of e-cigs’ vapor higher than that of water pot’s vapor.
Keep in my that I’m not sure. I just deduce from my knowledge. These could be wrong. Don’t experiment with anything and stop vaping.
Latest Answers