1. Liquids and Solids
Water

2. Objectives Describe the structure of a water molecule.
Explain the physical properties of water in terms of the intermolecular forces that exist between molecules.
Calculate the amount of heat energy absorbed or released when a quantity of water changes state.

3. Structure of Water Polar bonds sp3 hybridization 105o bond angle
Hydrogen bonding

4. Structure of Water
Liquid
Solid

5. Structure of Water

6. Physical Properties of Water
Water has a high melting (0oC) and boiling point (100oC)

7. Physical Properties of Water
Water has a high specific heat.
It can absorb or release large amounts of energy without its temperature changing significantly

8. Physical Properties of Water
Water has a high heat of vaporization.

9. Physical Properties of Water
Liquid water becomes less dense as it warms.
Ice is less dense than liquid water.

10. Phase Changes
Molar Heat of Fusion 6.01 KJ/mol Molar Heat of Vaporization KJ/mol

11. Heat Calculations
What quantity of heat is released when 506 g of liquid water freezes?
2. What mass of steam is required to release 4.97 x 105 KJ of heat energy on condensation?