1. Warm-Up 12/16/2016
A mixture of gases (NO2,CO2, SO2) is collected in a bottle. The partial pressure of NO2 is 1.25 atm, and the partial pressure of CO2 is 2.63 atm. If the total pressure of the gases is atm, what is the partial pressure of SO2?
A) 2.89 atm
B) 7.32 atm
C) 9.23 atm
D) atm

2. Example Problem
1. If [H+ ] = 1 x 10-5, what is the concentration of [(OH-)]?
Begin 5th, 7th

3. pH Scale
The pH scale was developed in an effort of compare the strengths of acids and bases
The pH scale runs from 0-14
pH < 7 are acidic
pH = 7 are neutral
pH > 7 are basic

4. Mathematical Definition of pH
pH (potential of Hydrogen) is defined as the negative logarithm of the hydrogen-ion concentration
pH = - log [H+]

5. Example
What is the pH of a solution in which
[H+] = 3.45 x 10-5?
Is the substance acidic, basic, or neutral?

6. Additional pH Examples
Calculate the pH values. Determine if each solution is acidic, basic, or neutral.
A. [H+] = 1 x 10-7
B. [H+] = 6.7 x 10-11
C. [H+] = 0.1
D. [H+] = x 10-9

7. Find the Following pH’s and tell if it is acidic, basic or neutral
Practice
Find the Following pH’s and tell if it is acidic, basic or neutral
[H+] = x 10-4
[H+] = 1 x 10-11
[H+] = 4.5 x 10-7

8. pH Values and Concentration
If the pH value is known the hydrogen ion concentration can be determined
[H+] = 10-pH

9. Example Problem # 1 What is the hydrogen ion concentration if pH = 3.4
pH = - log [H+]
3.4 = - log [H+]
= [H+]
3.98 x 10-4 = [H+]

10. Example Problem # 2
What is the Hydrogen Ion Concentration if the pH equals 8.75?
Answer = [H+] = 1.78 x 10-9

11. pOH( Potential of Hydroxide Ions)
pOH measures the amount of hydroxide ions
pOH is used to measure basicity
pOH = - log [OH-]
pH + pOH = 14

12. Practice
What is the pOH of a solution that contains x10-5 [OH-]?
What is the substance’s pH?

13. Complete the following chart

14. Complete the following chart

15. Practice Complete the following chart15

16. Practice Problems
Determine if each of the following solutions is acidic, basic, or neutral:
a. [H+] = 6 x 10-10
b. [OH-] = 3 x 10-2
c. [H+] = 2 x 10-7
d. [OH-] = 1 x 10-7
Begin 1st , 3rd

17. What is the pH and the pOH of the following?
1) M HCl
2) M NaOH
3).0025 M H2SO4
4) M Ca(OH)2

18. Molarity
A measurement of the concentration of a solution
Molarity (M)= is equal to the moles of solute (mol) per liter of solution
M = mol/ L

19. Practice
Calculate the molarity of a solution prepared by mixing 1.5 g of NaCl in mL of water.