The Challenge: Make Ice
Page: 1 2 3 4 5 6 7 8 9 10
So, if we are going to freeze our water to make ice, we will need to slow the
water molecules down by removing energy to the point where the hydrogen
bonds can hold the molecules closely together in a lattice.
The First Law of Thermodynamics says that energy cannot be created or
destroyed, only converted from one form to another. We can remove
energy from the water by placing it in contact with something cold.
We'll be using a cooling liquid.
transfers heat between the water and the cooling liquid. We don't
want to contaminate the water with the cooling liquid so we keep
them separate by putting the cooling liquid inside a container.
The container then sits in the water.
Energy from the water is transferred through the walls of the container
to the cooling liquid.
This is all in accordance with The
Second Law of Thermodynamics.
We need to make sure that as we 'suck' heat out of the water and into
our cooling liquid, we don't get more heat creeping into the water
from outside the container. If we use a cup made of polystyrene
as the container, it will insulate the water and prevent any more heat from getting in.