Does ice cool?
Name: Amber, Matt, Jason
Does ice cool a drink or does a drink warm the ice?
Heat moves from a warmer body to a cooler body. Thus heat
moves from the drink to the ice. When heat moves from the
drink, it gets cooler.
Heat is a transfer of energy on a microscopic scale. Temperature
is a measure of the average kinetic energy (energy of motion) of
the molecules present in a sample of matter. Thus, when heat moves
from the drink, the molecules in the drink have a lower kinetic
F. Brown in Tallahassee
Most of the cooling of the drink comes from the "latent heat
of melting" which the ice absorbs when it melts... I think
Both of these answers are basically correct
but I'd like to try to tie them together if I may.
Microscopically, the flow of heat between two phases
is a massive transfer of kinetic energy due to molecular
collisions. Now, if you dropped a block of cold aluminum into
a cup of warm water, ALL of the heat that flowed from the
"warm" water to the "cold" block would correspond to a
"slowing-down" of the water molecules (cooling) and a
"speeding-up" of the aluminum block's atoms (warming).
Nothing else happens in this situation, because the
amount of energy transferred is not enough to break the
covalent bonds holding the atoms in the block of aluminum
Now, if the cold block is ice instead of aluminum, the
heat that flows into the ice IS enough to break the
hydrogen bonds holding the molecules in the block of ice
together...or at least, some of it. Whether the ice
melts completely will depend on how much water and how much
ice there is in the glass...but some of it will melt, and
this allows a cube of ice dropped into the cup to absorb
more heat than the same mass of liquid water at the same temperature
would...due, as jade hawk says, to the "latent heat of melting."
So some cooling is due to melting, and some to equilibration.
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Update: June 2012