1. 2.2 Water

2. We need water Lubricate lungs to exhale Kidneys remove wastes
Lubricate joints and allows smooth movement
High specific heat (energy required to change water temperature)  regulate body temperature
High heat of vaporization (energy required to evaporate). Sweating allows for cooling.
And MORE

3. Water molecules
Formed by a polar covalent bond between an oxygen atom and two hydrogen atoms
Attraction between water molecules: hydrogen bond

4. Research
Read pages 47 – 49 of the Pearson textbook. 1. What does it mean that water has cohesive, adhesive, thermal and solvent properties? 2. What substances dissolve in water, and what substances do not?

5. 2.2 Water

6. Research
Read pages 47 – 49 of the Pearson textbook. 1. What does it mean that water has cohesive, adhesive, thermal and solvent properties? 2. What substances dissolve in water, and what substances do not?

7. Why do pennies float? Cohesion
hydrogen bonds between polar water molecules cause them to cohere
allowing for transpiration in plants moving water against gravity
allowing for animals such as water striders to walk over the surface of ponds even though they are denser than water

8. What other properties does water have?
Thermal properties
hydrogen bonds between polar water molecules cause water to resist change
high specific heat (energy required to change water temperature)
high heat of vaporization (energy required to boil water)
high heat of fusion (loss of energy required to freeze water)
Thus, water produces a stable environment for aquatic organisms

9. What other properties does water have?
Solvent properties
the polarity of water attracts, or dissolves, any other polar or charged particles by forming hydrogen bonds with them
Amino acids, glucose, ions (e.g. sodium chloride) oxygen are soluble in water because they are hydrophilic (polar) or have charges
Fat molecules and cholesterol are not soluble in water and are transported via lipoprotein