Properties of Water Lab What happened in this lab?

Station One

Penny & Water Properties shown: Cohesion: Water sticks to water to give the bubble effect and allow so much water to fit in a tiny space.

How does this relate to living things? Cohesion works due to hydrogen bonding between hydrogen and oxygen atoms in water. Water sticking to water allows a lot of water to fit in tiny spaces (cells and tubes).

Station Two

Wax Paper & Water & Oil Properties of water shown: Water is polar and wax is nonpolar (remember like only dissolves like) so the water just sits on the wax paper like a bead, when you drag them together they form a big bubble (cohesion: water sticking to water) and (adhesion, water sticking to wax paper) Oil is non-polar and so is wax, like dissolves like, so the oil dissolves through the paper, does not show the same properties as the water.

How does this relate to living things? Some nutrients (sugar), vitamins & minerals only dissolve in water because they are polar like water. (Ex: Vitamin C). This is why your blood is made of water not oil.

Station Three

Paper Clip in Water & Add Soap Properties of water shown: Paper clip floats because cohesion (water sticking to water) allows for surface tension to form. Paper clip sinks because the soap is non-polar and breaks the hydrogen bonds in water. (no more surface tension).

How is this important to living things? Allows very light organisms to walk on water without drowning. Shows how mixing nonpolar with polar destroys hydrogen bonds in water.

Station Four

Ice in Water & Alcohol Properties of water shown: Density & High Specific Heat Ice floats in water because it is less dense than water because the hydrogen bonds spread out as ice is formed. Ice sinks in alcohol because it is more dense than alcohol.

Why is this important to living things? Fish can survive in the water because ice floats in water (it is less dense) and insulates the bottom of the pond. (high specific heat: hydrogen bonds resist extreme changes in temp). Water at the bottom can stay in liquid form.

Station Five

Capillary Tube & Red Water Properties of water shown: Adhesion: The water rises up in the tube by sticking to the sides of the tube.

How is this important to living things? This is how a tree moves water from the ground to its leaves. The water sticks to the sides of the tubes in plants and the water can then rise. Also shows how blood (made of water) can move in out tube network in our bodies.

Solutions Water can stick to other things and dissolve through them the property of adhesion. This is how solutions are formed. Blood acts as a solvent dissolving polar solutes that we need to live (sugar, vitamins).