Properties of Properties of WaterWater

Mr. Luis A. VelázquezMr. Luis A. Velázquez

What is water?What is water?

Water also known as HWater also known as H22O is a O is a

molecule.molecule. Water is made of non-metals.Water is made of non-metals. Water is made out of two Water is made out of two

diatomic molecuels. Hdiatomic molecuels. H22 & O & O22

Properties of waterProperties of water The attraction between water molecules The attraction between water molecules

is called is called cohesioncohesion. . The attraction of the water molecule to The attraction of the water molecule to

other materials, like glass or soil , is other materials, like glass or soil , is called called adhesionadhesion. .

These also cause These also cause surface tensionsurface tension and and capillary actioncapillary action..

Water has a high surface tensionWater has a high surface tension

Because water is a polar molecule; it Because water is a polar molecule; it easily attracts other water molecules. easily attracts other water molecules.

This attraction causes the surface layer This attraction causes the surface layer of water molecules to act as a stretched of water molecules to act as a stretched film over the surface of the water. film over the surface of the water.

This property is known as This property is known as surface surface tension.tension.

Capillary ActionCapillary Action

Plants also take advantage of the great Plants also take advantage of the great attraction water has for itself and other attraction water has for itself and other molecules. molecules.

In fact, it is this property of water that In fact, it is this property of water that allows plants to get water from the ground. allows plants to get water from the ground. Water creep up the thin tubes in plant Water creep up the thin tubes in plant roots and stemsroots and stems

Water has a high heat of Water has a high heat of vaporizationvaporization

Because water strongly attracts other water molecules; Because water strongly attracts other water molecules; it takes a lot of energy to make water evaporate. it takes a lot of energy to make water evaporate.

As water heats, its molecules vibrate faster and faster. As water heats, its molecules vibrate faster and faster. As more heat is applied, surface molecules begin to As more heat is applied, surface molecules begin to separate from the rest and evaporate in to the air. separate from the rest and evaporate in to the air.

This high heat of vaporization helps cool the human This high heat of vaporization helps cool the human body. When sweat evaporates from the human skin, its body. When sweat evaporates from the human skin, its draws away the heat of vaporization from the body draws away the heat of vaporization from the body itself, thus helping keep the body cool.itself, thus helping keep the body cool.

Resistance to changeResistance to change

Water resist temperature Water resist temperature changes.changes.

Water requires more heat to Water requires more heat to increase its temperature than do increase its temperature than do most other common substances.most other common substances.

Water expands when it freezesWater expands when it freezes

Water is one of the few Water is one of the few substances that expand when it substances that expand when it freezes. freezes.

Because of this property, ice is Because of this property, ice is less dense than liquid water and less dense than liquid water and floats as it forms in a pond. floats as it forms in a pond.

Polar MoleculePolar Molecule

Water is consider a polar molecule.Water is consider a polar molecule. This means that water molecule has two This means that water molecule has two

poles. ( Positive & negative)poles. ( Positive & negative) Water is made of two atoms of hydrogen Water is made of two atoms of hydrogen

and one of oxygen.and one of oxygen. Hydrogen behave as a positive pole.Hydrogen behave as a positive pole. Oxygen behaves as a negative pole.Oxygen behaves as a negative pole.

Hydrogen Hydrogen

Oxygen

++

-

What is a polar Molecule?

Interesting informationInteresting information

Water is the most common liquid in the world.Water is the most common liquid in the world. Water makes up Water makes up 78%78% of the human body. of the human body. 70% of the Earth is cover with water.70% of the Earth is cover with water. When water reach the temperature of When water reach the temperature of 3838FF

water expands water expands 9%9% Water is considered the universal solvent can Water is considered the universal solvent can

dissolve almost every thing in earth.dissolve almost every thing in earth.