Now that it’s getting cold out you’ve probably noticed you can see your breath outside again. I noticed it for the first time this season last weekend. But why does this happen?
Here is the best explanation why that I found via childrensmuseum.org
When you breathe in (inhale), your body takes in oxygen from the air. And when you breathe out (exhale), your lungs put carbon dioxide back into the air.
However, the breath you exhale doesn’t only contain carbon dioxide. It also contains moisture from your mouth and lungs. This moisture is in the form of water vapor, the gas form of water.
The environment inside of your lungs is warm, providing the energy needed for water to stay in its gas form.
when you step outside into cold temperatures and exhale, the cold air around you doesn’t give off enough energy to keep the water molecules moving around, and they end up packing themselves close together. This causes the moisture in your breath to condense (change into either liquid or solid forms of water), forming a little cloud in the air.
You’ll usually be able to see your breath when it gets to 45 degrees Fahrenheit and below.
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