the wonder of water physical & chemical properties

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The Wonder of Water Physical & Chemical Properties

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The Wonder of Water

Physical & Chemical Properties

Water expands when it freezes and becomes less dense unlike most other substances.

Long legged bugs called “water striders” can skate along the surface of a body of water because:

The hydrogen of one water molecule is attracted to the oxygen of another

water molecule like opposite poles of a

magnet are!

The attraction is called a Hydrogen bond and the result is that water molecules demonstrate

“cohesion” causing water to have a “strong surface” called “surface tension”.

When water vapor cools it takes up less space and contracts, allowing water molecules to stick to one another forming clouds and precipitation.

More things can be dissolved in water than in strong acid.

The movement of liquid water along with its ability to form hydrogen bonds, allows water to pull substances apart and dissolve them better but not always faster then an acids!

It takes more energy to heat cold water to 212o F (100 o C) than it does to change “boiling” water at 212o F (100 o C) to steam.

It takes 5x as much energy to turn boiling water into steam then it takes raise cool water to boiling point @ 212o F .

Water is the most common compound on Earth.

More then 70% of the earth is covered in water. 66% of our bodies are made of water.

Sea water is slightly more alkaline or basic (the pH value is higher) than most natural fresh water.

Neutral water (such as distilled water) has a pH of 7, which is in the middle of being acidic and alkaline. Seawater happens to be slightly alkaline (basic), with a pH of about 8. Most natural water has a pH of between 6-8, and acid rain can have a pH as low as 4.  

Water boils & evaporates quicker at high altitude, than at the sea level.

At sea level water boils at 100o C. At 2,400 m, water boils at 92o C. This is because as the altitude gets higher, the lower air pressure makes it easier for the water molecules to break their bonds and attraction to each other and, thus, it boils more easily.

or 202 oF @ 7,800 ft

212 oF

Water is the only substance that is found naturally on earth in three forms: liquid, gas, solid.

Water can commonly be seen in the solid, liquid and gaseous state on Earth.

Water is known as the universal solvent.

A substance that has the ability to dissolve both bases and acids, such as water is called a “universal solvent. Everything else dissolves in water as well... stone, iron, pots, pans, plates, sugar, salt, and coffee beans.