If water boils at 100 degrees C then why do we see steam when we shower/wash our hands sometimes?
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Because water doesn’t have to boil to evaporate. This is a very, very common question on this sub; please search before posting.
H2O at gas state is actually invisible. What you see in steam is actually micro droplets of water, at a temperature below 100ºC. Clouds, for example, is micro droplets of water in the air at a temperature far below 100 ºC, and also has the same visual aspect of steam. At Gaseous state, molecules of h2O are too spaced from each others to reflect light, so that explains why we can see them. Hope this helps
It’s just evaporated water, not steam. When warm moist air mixes with the surrounding cold air, the water can condense into what is basically a small cloud. That’s why it usually happens when it’s rather cold.
The hotter liquid water is, the faster it wants to evaporate. The hotter air is, the more water vapor it can contain.
So washing your hands with hot water will create make water want to evaporate into the warm air right next to the water. But when that water cools down (by mixing with the cooler air all around the room), the water vapor starts to condense back to liquid. These tiny liquid droplets are what we see and call steam. *True* steam, evaporated water or water vapor, is invisible.
evaporation can happen at nearly any temperature found on earth.
the relative temperature of the water, the humidity of the air(how much water is in it) and pressure of the air(low pressure boils water faster) can cause evaporation.
when you see steam your seeing condensed water not water vapor.
when the air in the bathroom gets hit with warm water the water evaporates into thin air that was warmed by the water, but as the high humidity air cools, or contacts something cool the ‘dew point’ is reached(water is squeezed out of the air by pressure cooling by constricting. the coolness lessens the amount of water it can hold and the water condenses into tiny droplets(just like clouds) this is how steam becomes visable.
When water boils to steam, the steam is actually clear and colorless. When you see a fog of “steam”, you are actually seeing the steam turning back into liquid water droplets. Water evaporates below the boiling point. The warmer it is, the quicker it evaporates. So hot water below the boiling point is evaporating quite quickly. As the evaporated water cools down, it recondenses back into tiny liquid droplets that we see as a fog.
What we call Temperature is a measurement for how fast the molecules in a substance move. Not all molecules move at the same speed. Some are faster some are slower but we only measure the average speed.
What happens when water evaporates is that molecules get fast enough to leave the liquid phase and go into the surrounding air. Some molecules will reach this speed at significantly lower temperatures than 100°C.
If water molecules come into cool air they loose some of their energy to the air molecules and become slower. If they get slow enough they will start forming microscopic drops of water. Those drops is what we see as fog.
When you wash your hands or shower with hot water there are a lot of molecules that can leave the liquid phase. A lot of the water will condensate again because the air is a lot cooler than the water
Temperature is an *average* of the kinetic energy of the molecules. What makes a temperature high, is all the molecules racing around bumping into one another.
This means that in a cooler body of water, *some* of the molecules can be going slower, and some can be going faster. Perhaps 2 water molecules slam into a 3rd at the same time and give it double the energy. That molecule will get ejected at high speed and vaporize — but the overall temperature (the average) of the liquid water won’t increase. In fact, it will get slightly lower because that 3rd molecule just left the liquid and took the energy from the first 2 molecules with it.
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