Which one would cool down faster: a 100ml of hot water, a 300ml of hot water or a 500ml of hot water? Why?

The parameters, according to an e mail sent to me, are, same surface area, same type of containers and same starting temp. Which will become cool FIRST.

Since the surface area is the same, the smallest volume will become cool the fastest. Why? Less adjacent Molecular heat exchange. Heat is radiated or physically transfered from Molecule to Molecule like a Quarterback handing off a Football. If there is less "players" (Molecules) on the field the less "hand-offs" necessary and therefore less time involved. Conversely, if one started out with equal volumes of Water, the hotter one WOULD cool at a faster RATE.

Newton's Law of Cooling states that the RATE of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature (i.e. the temperature of its surroundings).

https://www.slader.com/discussion/question/newtons-law-of-cooling
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