Properties of Water

Water Water is one of the most important molecules to life In fact, when scientists are trying to determine if a planet could support life, they try to find water on that planet

Polarity Many of water’s properties stem from its structure Water has a definite structure of H20 Many people call it a “Mickey Mouse”

Polarity The structure of water has an ability to affect other water molecules Because of the position of the molecules, water has slightly uneven charges Polarity is the term given to molecules that have uneven distribution to their charges

Polarity The oxygen atom in water has a greater attraction to electrons This means that the electrons are slightly more attracted to the oxygen The hydrogen atoms have a lesser attraction to their electrons This means that the electrons are farther away from the hydrogen

Polarity Because of how the electrons are pulled, the water atom has uneven charges Since the electrons are more attracted to the oxygen, it has a slightly negative charge Since the electrons are farther away from the hydrogen it has a slightly positive charge

Hydrogen Bonding Since water is polar and it has slight negative and positive charges it has a special structure The nature of the uneven charges causes the slightly negative charges to be attracted to the slightly positive charges

Hydrogen Bonding When water molecules are attracted to each other, it is called Hydrogen Bonding Hydrogen Bonding is when a hydrogen atom is attracted to the partial charge of another polar molecule

Cohesion and Adhesion Water molecules will stick to each other due to their hydrogen bonds Think of your shower, what do the walls look like after you use it? How do you remove the water from the shower after you use it?

Cohesion and Adhesion Cohesion is the process of water sticking to itself due to its polar bonds It will cause water to tend to stick to itself

Cohesion and Adhesion Surface Tension is a property of cohesion It causes the surface of the water to be pulled towards the remainder of the water The water forms a slight “skin” that pulls back towards the rest of the water

Cohesion and Adhesion Adhesion is the attraction between two different kinds of molecules Water will often be attracted to different materials because of its structure

Cohesion and Adhesion With both the processes of cohesion and adhesion, water climbs up small tubes Why do you think water climbs up small tubes? This process is called Capillary Action

Demo

Temperature Since water is a polar molecule, it is very attracted to other water molecules It does not want to be pulled away from other water molecules It takes A LOT of energy to move water molecules away from each other

Temperature Water does not often change its temperature It takes a lot of heat to break the hydrogen bonds of water Breaking the bonds would allow water molecules to move away from each other