Eli5: Why the viscosity of oil decreases when it gets heat up?
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Using my general knowledge here. I could be a dumb dumb and be way off….
Heat causes the molecules to move more. When they move more, they need more space. More space between the molecules means less viscosity.
Oil isn’t special. The viscosity of all fluids decreases as they heat up. It’s a property of the internal attractions of the fluid, and when you heat it up, they don’t get as much time to attract because all the molecules are flying around faster.
Oils are made of molecular chains which can vary in length depending on the oil. The viscosity increases with molecule length because for it to flow the molecules have to move past each other and overcome the attractive forces holding them together.
When you heat up the oil, the molecules have more energy which essentially means they jiggle more and therefore can overcome attractive forces and move past each other more easily. This translates to less viscosity.
Edit: typos
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