Basic Energy Question- Hot and Cold Water

In summary, the conversation discusses the Mpemba effect, which is the phenomenon of hot water freezing before cold water. The jury is still out on whether this actually happens, and it is believed to occur only under certain conditions. Additionally, the conversation touches on the different ice structures that can form when water freezes, with amorphous solid water being the most common on other planets and moons.
  • #1
Jshua Monkoe
8
0
Why actually does "hot" water freeze before cold water? This sounds very basic but believe me I can't come up with a single feasible reason
 
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  • #2
You refer to teh so called Mpemba effect. The jury is still out on this one. Even if it happens it happens only sometimes, when some particular (and not well defined) conditions are meet.
 
  • #3
Borek said:
You refer to teh so called Mpemba effect. The jury is still out on this one. Even if it happens it happens only sometimes, when some particular (and not well defined) conditions are meet.

Mmh, interesting.
Just looked up the Mpemba effect.
Weird thing, there seems to be something missing in the wiki article.

I know that water freezing can result in different ice structures (15 types).
It would make a difference which ice structure water freezes in.
When super cooled water freezes "wild" - no structure (amorphous solid water or ASW).
This is how water occurs on other planets and moons.
I imagine it takes less (loss of) energy to freeze that way.
 

1. What is the difference between hot and cold water?

The main difference between hot and cold water is the temperature. Hot water has a higher temperature than cold water. The exact temperature range for both hot and cold water may vary depending on the source and the intended use.

2. Does hot water freeze faster than cold water?

Contrary to popular belief, hot water does not freeze faster than cold water. This phenomenon is known as the Mpemba effect and it occurs under certain conditions, such as using very hot water and very cold temperatures. In most cases, cold water will freeze faster than hot water.

3. Is hot water more energy efficient than cold water?

Yes, hot water is generally more energy efficient than cold water. This is because warm or hot water requires less energy to heat up than cold water. However, the overall energy efficiency will also depend on factors such as the type of water heater and insulation.

4. Why does hot water feel different than cold water?

Hot water feels different than cold water due to its higher temperature. Our skin contains temperature receptors that detect the difference in temperature between hot and cold water. Additionally, hot water can also cause blood vessels to dilate, which can lead to a sensation of warmth.

5. Can hot and cold water mix?

Yes, hot and cold water can mix together. When two different temperatures of water are mixed, the resulting temperature will be somewhere in between the two original temperatures. This is known as thermal equilibrium.

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