There are lots of benefits of using a higher temperature of water for cleaning. List them!


closed as off-topic by John Rennie, Aaron Stevens, user191954, Jon Custer, JMac Nov 5 '18 at 19:17

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  • $\begingroup$ Could you mention some examples? $\endgroup$ – Steeven Nov 5 '18 at 9:56
  • $\begingroup$ Hot water has faster moving molecules than cold water. (The molecular speed translates into heat.) $\endgroup$ – A guy who likes train Nov 5 '18 at 10:04
  • 3
    $\begingroup$ I'm voting to close this question as off-topic because it is not a question about physics $\endgroup$ – John Rennie Nov 5 '18 at 10:09
  • $\begingroup$ This isn't really physics:perhaps is a bit engineering and chemistry-ish. A question about how things work is more likely to be appropriate. $\endgroup$ – user191954 Nov 5 '18 at 11:59

Effects that help in "cleaning" (i.e. : bring substances into water based solutions):

You can think of everything mechanically:

  • Certain chemicals improve solubility of hydrophobic compounds (See wiki/soap)
  • Time (it takes time to reach an equilibrium state)
  • Temperature (Higher temperature is better - this is your question. Stay whith me)
  • Mechanical agitation (scrubbing helps to loosen "junks" and break up big junks into smaller pieces).

What is Temperature?

Temperature is the movement of the individual pieces of a substance: In hot water, the water molecules move stronger (e.g. they translate faster from one point to antoher. They bump into each other harder). Think of the 4th point above: It's like microscopic mechanical agitation.

This was one point to your question.

Another point (much less important) is:

If a given amount of water is extremely hot such that it is boiling, or if a give amount of water has a high temperature gradient, then convection will happen: I.e. bunches of water will move in bulk. This could under certain circumstances improve "cleaning" because "fresh" water (i.e. water with lower concentration of the substance that is considered "dirty") is brought in.


Hot water's surface tension is lower than that of cold water. This allows it to penetrate deeper into cracks and crevices and more easily solubilize poorly-wetting substances like oily dirt, etc.


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