From pages 33-34
• What coefficients must be places in the blanks
that balance this chemical reaction?
–C6H12O6
____ C2H6O
+ ___ CO2
From pages 33-34
• Which of the following statements correctly
describes any chemical reaction that has
reached equilibrium?
– The concentration of products equals the
concentration of reactants.
– The rate of the forward reaction equals the rate of
the reverse reaction.
– Both forward and reverse reactions have halted.
– The reaction is now irreversible.
– No reactants remain.
Properties of
Water
Facts
• Cells are about 70-95% water
• Most cells are surrounded by water
• Water is a main reactant in a lot of chemical
reactions of life
• Exists in all 3 states of matter
– Solid (ice), liquid, vapor
Polarity
•
•
•
•
What is electronegativity?
What is nonpolar?
What is polar?
Draw and explain Figure 2.11
• PAGE 29 (37-top 38)
Figure 2.11
Figure 2.11
• Draw and explain Figure 3.1 (Page 38)
Figure 3.1
• Polar covalent bond
• 2 H bonded to 1 O
• Electrons shared
unevenly allowing
for H bonding
between water
molecules
• H bonds=weak
covalent bond
Assignment
• Once I assign you a group, obtain
a computer. Go to our classroom
and open the assignment titled
“Water properties”.
Properties of WAter
• Surface Tension
• Capillary Action
• High specific heat capacity
– Ability to Stabilize Temperature
– High heat of vaporization/evaporative cooling
• Expansion upon freezing
• Versatility as a solvent
Surface tension
• What characteristic leads to the surface
tension of water?
• What bonds form the invisible film on the
surface of water?
• Are these bonds only found on the surface?
Capillary action
• Define capillary action.
• What characteristic(s) lead to this property?
• Relate this to both straws and plant hydration.
Specific heat
• What is the “book definition” of specific heat
capacity?
• HOW is water able to hold on to heat?
• Does sweating cool the body? Explain.
• How is high specific heat of water beneficial to
life on Earth?
Expansion upon
freezing
• What is the movement of molecules in a
frozen solid state?
• Answer expand or contract:
– Water moving above 4 degrees _____
– Water moving from 0 degrees to 4 degrees _____
– Water moving from 4 degrees to 0 degrees _____
– Water moving below 0 degrees _____
• In a crystalline structure of ice, each water
molecule has how many “other partners”?
Water is the
solvent of life
•
•
•
•
•
What is a solution?
What is a solvent?
What is a solute?
What is an aqueous solution?
What quality of water enables water to be such
a versatile solvent?
Figure 3.7
• Draw and explain Figure 3.7 (page 42).
Hydrophilic
vs
Hydrophobic
• What is hydrophilic?
• What is hydrophobic?
• PAGE 42-43