1. Warm Up #7 1. Is magnesium hydroxide a weak or strong base?
You are INITIALLY given 98.5 grams of Magnesium Hydroxide, Mg(OH)2, in a 500 mL solution with water. Kb = 8.9x10-3
1. Is magnesium hydroxide a weak or strong base?
2. What is the concentration of Mg(OH)2?
3. What is the [OH-]? [YOU NEED ICE TABLE]
4. What is the pH of this substance?

2. Warm Up #7
10 grams NH3, a weak base, reacts with water to make a L solution at equilibrium. The Kb of NH3 is 1.8x10-5
Calculate [NH3]…M = mol/L
Show the reaction between NH3 and water, and set up a Kb equation.
Solve for the [OH-]. With this, solve for the pH of your base.

3. Chapter 19.5
Hydrolysis of a Salt

4. Hydrolysis…what? Hydrolysis – adding water
When adding water to a salt you get…
One acid
One base
Ex. NaCl + HOH  NaOH + HCl
NaOH = base, HCl = acid
DOUBLE REPLACEMENT

5. Strong Acids and Bases Strong Acids: HCl, HBr, HI, HNO3, HClO3, H2SO4
Strong Bases: Any Alkali/alkaline metal with OH (except Mg)

6. pH of the Salts Strong acid and Strong base Strong acid and Weak base
NEUTRAL pH
Strong acid and Weak base
ACIDIC pH
Weak acid and Strong base
BASIC pH
Weak acid and Weak base
UNKNOWN pH

7. Warm Up #9 You add water to Al(NO3)3:
Show this chemical reaction, and balance the equation.
On the products side, label the acid and the base (including their names). Also, include the strength of each (weak/strong).
What will the pH of this salt be (acidic/basic)? How do you know?