Hydrogen (+) Positive H Hydrogen (+) Positive H Oxygen (-) Negative O Water Molecule

Water is a Polar Molecule Water is a polar molecule. It has a (+) positive and a (-) negative end. As a result, each water molecule is like a little magnet. This property causes water molecules to be very attracted to each other. It also causes water molecules to be attracted to many other different polar molecules. Water’s polarity is responsible for its unique properties that make it essential for life.

Water: The Universal Solvent Capable of dissolving a variety of substances Dissolves more substances than any other liquid Wherever water goes, either through the ground or through our bodies, it takes along valuable chemicals, minerals, and nutrients.

Dissolving Salt Water can become so heavily attracted to other polar molecules, like salt (NaCl), that it can disrupt the attractive forces that hold the sodium and chloride in the salt molecule together and, thus, dissolve it

Specific Heat Capacity The quantity of heat required to raise the temperature of a unit mass of substance by one degree Celsius. Water has a high specific heat meaning it takes a lot of heat to make it hot. Substance Specific Heat (J/g o C) Air 1.01 Vegetable Oil1.67 Rubbing Alcohol2.60 Milk3.93 Water 4.18

How does that benefit life? Water changes temperature very slowly Helps us maintain our body temperature Regulates the temperature in the atmosphere Fish do not die because the temperature of water is able to stay somewhat the same from day to night Why is the high specific heat capacity of water important?

Hydrogen Bonding in Water Hydrogen bonds hold water molecules together (Animation).Animation In water, a hydrogen bond is a relatively weak attraction between the positively charged H atom in one molecule and the negatively charged O atom from another molecule. Hydrogen bonds are responsible for two types of attractive forces in water: Cohesion and Adhesion

Cohesion Attraction between like molecules Water’s cohesiveness causes it to ball up into a sphere and stick together.

Surface Tension Property caused by water’s cohesive nature Allows small objects to “float” on the surface as long as they do not break the surface

Adhesion Attraction between different molecules Water’s adhesive properties cause it to spread out across and stick to the surface of an unwaxed car. Water adheres well to a painted surface but not to wax.

Capillary Action Tendency for a liquid to rise in narrow tubes Occurs as a result of adhesion and cohesion Capillary action causes water to move high into trees

Properties of water in space