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Used almost universally for purification, cleansing & blessing
The life and climate of Earth as we know it would not exist without the unique properties of water.
The unique properties of water are based on the chemical makeup of the water molecule.
In order to understand, these unique properties and the makeup of a water molecule, let’s explore a little basic chemistry.
An atom is: The smallest unit of a pure substance
(element) which cannot be broken down by ordinary chemical means
Composed of protons, neutrons and electrons
Elemental units of which everything is made
Atomic Diameters: one to a few hundred millionths of an inch
Atoms bonded together
Bonds: forces that hold atoms together form when atoms with correct fit collide with
sufficient force store energy
Covalent bond: atoms collide and electrons rearrange so that some of the electrons are shared by the two atoms
Polar covalent bond: unequal sharing of electrons
Attraction between a hydrogen atom and an atom such as oxygen or nitrogen that is either part of another molecule or located at a distant site on the same molecule.
Both the hydrogen atom and the other atom must be involved in a polar covalent bond
This causes water molecules to “stick together”
Specific heat: the amount of heat required to raise or lower the temperature of 1 gram of substance 1 degree C.
A lot of heat energy is required to break hydrogen bonds, therefore water resists temperature change.
When water is heated, most of the heat is used to break hydrogen bonds and not much is left over to raise the temperature of the water.
In other words, water can absorb a lot of heat with little change in temperature.
Because of this water acts as a thermal buffer.
Because water acts as a thermal buffer (aka has high thermal capacity),
Water in the ocean resists temperature change by heating and cooling more slowly
This results in a lower range of temperature in the ocean temperatures than in the atmosphere
Ocean temperatures vary by no more than 2°C (3.5°F)
This creates a hospitable environment for life. Especially in coastal areas which experience warmer
winters and cooler summers due to proximity to ocean.
Water is described as having a high thermal capacity
It requires energy to change statesMelting
Solid to liquid Heat of fusionEvaporation
Liquid to gas Heat of vaporizationCondensation
Gas to liquid Heat of condensationFreezing
Liquid to solid Heat of fusionSublimation
Solid to gas Heat of sublimation
Heat of vaporization: The amount of heat required for 1 gram of a substance to be converted from a liquid to a gas. Hydrogen bonds make it difficult for water molecules to
escape the liquid state and are responsible for water's high heat of vaporization.
The hydrogen bonds must be broken before water can evaporate and this requires considerable energy.
Because water has a high heat of vaporization:
It helps our bodies and our planet to maintain our temperature within a tolerable range.
When we get hot and sweat, water evaporates from our skin and cools us. Since the evaporation of water requires a considerable amount of energy, it is very effective in cooling us.
Water helps moderate global climate by absorbing solar
radiation and dissipating the heat by evaporation of surface water.
Most substances increase in density as temperature decreases because the molecules making up the substance begin to move more slowly and get closer together.
Water is unique in the way temperature affects its density. The density of water increases as it is cooled to 4
degrees C and then its density begins to decrease as the
temperature decreases to 0 degrees C, the freezing point of water.
As the freezing point is approached, hydrogen bonds relax and form a crystal lattice that keeps molecules further apart than they are in liquid water.
This is the reason why ice floats and ponds don't freeze solid.