1. Chemistry of Life
Properties Of Water

2. Properties of water: cohesion, adhesion, heat capacity, solvent
Objective
I can explain how the properties of water contribute to the maintenance of cells and living organisms.
Properties of water: cohesion, adhesion, heat capacity, solvent

3. Name the 4 macromolecules and their functions.
Starter
Name the 4 macromolecules and their functions.

4. Make 5 observations about the characteristics or behavior that water exhibits.

5. Water Rotation Lab

6. Importance of Water Water makes up 70-95% of most living organisms
All the chemical reaction s of life are carried out in water-based fluids

7. Water is a Polar Molecule
H2O – the oxygen atom shares its electrons with hydrogen in an unequal manner
Polarity: a separation of charge into distinct + and – regions.
The slight + charge of a hydrogen atom is drawn to the slight – charge of the oxygen atom. This type of interaction is called a hydrogen bond.

8. Hydrogen Bonds Weak bonds
Hydrogen bonds are important to organisms because they help to hold large molecules together
Hydrogen bonds give water its unique properties

9. Properties of Water
Cohesion
Adhesion
Heat Capacity
Solvent Properties

10. Cohesion
Cohesion: molecules of the same substance resist being separated from one another
Water molecules stick to other water molecules
Water molecules tend to clump together – water drops, surface tension

11. Adhesion
Adhesion: molecules of 1 kind are attracted to molecules of another kind
Allows water to cling to the sides of a container that hold it
Responsible for capillary action

12. Heat Capacity
Heat Capacity: the amount of heat needed to raise the temperature by 1 degree
Water is able to absorb a large amount of heat before changing phase or boiling – temperature stability
Water is like an insulator, it helps maintain a steady environment when conditions fluctuate

13. Heat of Vaporization
Heat of vaporization: the amount of energy required for a substance to change from a liquid to a gas
As water molecules evaporate, the surface they evaporate from gets cooler, a process called evaporative cooling.
In living organisms, the evaporation of sweat cools the body to maintain a steady temperature.

14. Solvent Solvent: liquid that can dissolve other substance
Solute: a dissolved substance
Solution: a mixture of solute and solvent

15. Universal Solvent
Ionic solids such as NaCl dissolve in water because waters hydrogen bonds are stronger than the ionic bonds. Water molecules tug the ions apart and surround each one.

16. Recap Video: Properties of Water

17. Properties of water: cohesion, adhesion, heat capacity, solvent
Objective
I can explain how the properties of water contribute to the maintenance of cells and living organisms.
Properties of water: cohesion, adhesion, heat capacity, solvent