Boiling Liquids

[bednobs]

whenever i am heating liquid on the stove, as i am cooking, there is not much steam. However, as soon s i turn the gas off loads of steam. Why?

[Svejk]

The heat warms the air above the pan and stops the water vapour condensing into steam.
If you shower in a cold room, it'll be full of steam, but not in a hot one.

[Old_Geezer]

Ah so that's the reason I don't get steamy bathrooms as I used to as a kid !

[Svejk]

Steady on, og.

[Buenchico]

True 'steam' (i.e. water in gaseous form) is invisible. What most people think of as 'steam' is actually water vapour (i.e. droplets of water suspended in air).

If you look at the spout of a kettle full of boiling water you'll see that the gas immediately above the spout is clear. It's only a bit further out that it condenses to water vapour as it cools.

Similarly, the surface of your liquid in the pan has clear steam above it (although you'll probably see water vapour further away, where its cooler, such as the mist on your windows). Once you turn the heat off the remaining (invisible) steam quickly condenses to (visible) water vapour.

[bednobs]

thank you boys, that has explained it to me perfectly. sorry i can't give you all BA

[Old_Geezer]

Someone's been watching QI.

[leesajohnson]

A boiling liquid expanding vapour explosion is an explosion/storm caused by the rupture of a vessel/watercraft containing a pressurized liquid above its boiling point.