1. Solution Concentration: Molarity
Molarity = moles solute per liter of solution
0.30 mol NH3 dissolved in L Concentration =
Written like: [NH3] = 0.60 M

2. pH: Quantitative Measure of Acidity
Acidity is related to concentration of H+
pH = -log[H+]
[H+] = 10-pH

3. pH Scale
In pure water, a few molecules ionize to form H+ and OH– H2O  OH– + H+
In acidic and basic solutions, these concentrations are not equal acidic: [H+] > [OH–] basic: [OH–] > [H+] neutral: [H+] = [OH–]

4. pH Scale Measure how much H+ is in a solution using pH
pH < 7.0 = acidic
pH = 7.0 = neutral
pH > 7.0 = basic
Measure of H+ and OH– concentration (moles per liter) in a solution
As acidity increases, pH decreases

5. pH = –log [H+] The pH scale is logarithmic: [H+], mol/L -log[H+]
log(101) = log(100) = log(10-1) = –1 -log(10-2) = log(10-4) = 4 1 x –9 -log(10-9) = 9

6. [H+] pH Calculations What is pH if [H+] = 10–5 M?
Is a solution with [H+] = 10–8 M? Acidic or basic?
What is pH if [H+] = M?
What is [H+] if pH = 4.68?

7. Molarity is a conversion factor
Moles Liters

12. Solution Stoichiometry
Example 1.
What is mass of PbCrO4 produced when 50.0 mL
of a M Pb(NO3)2 solution is mixed with an
excess of M K2CrO4?

14. CaCO3 + 2 HNO3  Ca(NO3)2 + CO2 + H2O
Calculate the volume (in mL) of M HNO3 needed to react completely with 6.35 g of CaCO3.
CaCO HNO3  Ca(NO3)2 + CO2 + H2O

16. Titration Example Problems: Just like your lab!
1. Standardizing an NaOH solution using a “primary standard”
A solution of sodium hydroxide is “standardized” by titration using solid
oxalic acid, H2C2O4, as the acid. It is found that 24.5 mL of the NaOH
solution is needed to react completely with 2.05 g of oxalic acid.
What is the concentration of the NaOH solution?
H2C2O4(aq) + 2 NaOH  2 H2O(l) + Na2C2O4(aq)