1) Please pick up a copy of the powerpoint notes.

Water

Chemical reactions of all living things take place in aqueous environments.

Water has unique properties that make it one of the most important compounds found in living things.

#1 Water is Polar

Even though the overall charge of water is neutral, the distribution of the electrical charge is uneven.

Consider the relative number of protons and electrons in each atom. Which atom has the most protons?

The hydrogen atoms have a slightly positive charge. The oxygen atom has a slightly negative charge.

Polar means that water simply has an uneven pattern of charge. This property makes water very good at dissolving other substances. Including protein, sugars, and NaCl.

#2 Hydrogen Bonding

Hydrogen Bonding A bond that occurs between water molecules as a result of polarity. Relatively weak bond that is easily broken. Causes molecules to stick to each other and other objects/substances.

Cohesion is an attractive force between particles that are the same.

Adhesion is an attractive force between unlike substances.

Capillarity is a property of water in which adhesion and cohesion work together to move water upward against gravity.

Capillarity

#3 High Specific Heat

Water must gain or lose a large amount of heat for its temperature to change.

How is this beneficial to life?

Water moves in cycles