when a cold water bottle (like from a fridge, etc.) cools down, why does it become wet on the outside of the bottle?


when a cold water bottle (like from a fridge, etc.) cools down, why does it become wet on the outside of the bottle?

In: 1

You mean when it warms up?

Cold air can’t hold as much moisture as warm air. The air that is in contact with the cold glass losses extra water as condensation as it rapidly cools.

Cold surface. Outside air has water vapor in it. When moist air hits Cold surfaces condensation forms.

There is water in the air around you.

Heat is energy.

Cold is the absence of heat.

When water has a lot of energy, it is a gas.

When water has less energy, it becomes a liquid.

The water in the glass has very little heat. That is, it has very little energy.

The water in the air has a lot of energy.

When the water molecules in the warmer air hit the side of the colder glass, they transfer some energy into the water in the glass and slow down. Some slow down enough to “stick.”

Those “stuck” water molecules make it easier for other water molecules to stick.

As more and more water molecules hit the glass and transfer their heat into the glass, they lose so much energy that they can’t be a gas anymore and so start to become liquid water on the side of the glass!

This is also why you see “fog” when you open the freezer. The cold air falling out of it meets the watmer air 8n the room and some of the water tries to squeeze out of the air for a moment, the lack of energy making some of the water molecules just start to stick to themselves and become heavy.

The water you find on the outside of the bottle does not come from inside the bottle.

The air around us all of the time has water in it. Sometimes only a little bit (low humidity air) sometimes quite a lot (high humidity air). One of the factors that determines how much water the air can hold is the temperature of the air. Colder air can hold less water than warmer air.

So, when you take that cold bottle and put it on the table, it immediately starts to cool the air around it. That air has water inside of it, and as the air cools it starts to have to much water. So that water has got to get out of the air somehow. And it lands on the bottle itself, since that’s where the cold air is coldest.

The water on the outside of the bottle is coming from the air around the bottle. That air is losing it’s water because the bottle is making the air cold.

This also explains why if your cold bottle contains beer and not water the drops that form on the outside are water and not beer. And also explains what morning due is, it’s the overnight air getting colder and letting out it’s water onto the grass.