Question

What happens to the average kinetic energy of water molecules as water freezes?

Answer 1

Water has distinct chemical properties in all three states of matter – the solid state , the liquid state, and the gaseous state. This is due to the fact that the water molecules' have the ability to form hydrogen bonds with one another.

Complete answer:
Water has two Hydrogen atoms and one Oxygen atom that make up the water molecule. Liquid water is made up of polar molecules linked by hydrogen bonds. When we think about water, we generally think of it as a liquid. Water, on the other hand, will travel through all states of matter. It may be a gas as steam, a liquid as water, or a solid as ice.
When the state of water changes, the average kinetic energy of the water molecules also changes.
We must know that the total value of the kinetic energy of molecules in random motion is measured by temperature. So, the relation between the temperature and the kinetic energy of the molecule is given by the equation:
$K.{E_{av}} = \dfrac{3}{2}RT$
Here,
$K.{E_{av}}$is the Kinetic Energy,
$T$is the temperature,
And R is the gas constant.
This equation shows that the average kinetic energy is proportional to the temperature of water.
When water freezes, the temperature of the water molecules reduce. By the relation established above, the average kinetic energy of the water molecules also reduces.
Thus, the average kinetic energy of water molecules reduces as water freezes.

Note:
When the molecules of a liquid get so cold that they slow down enough to hold onto each other and form a stable crystal, this is known as freezing. This occurs at $32$degrees Fahrenheit for fresh water, and unlike most other solids, ice expands and is less compact than water.