Acid Base Practice Problems:

Today:

Next Week: REVIEW
FOR
FINAL EXAM:
◦ Logarithms & pH
Calculations
◦ Acid-Base Titrations
◦ Bring your questions
◦ Indicators for monitoring
◦ Pizza Party NEXT THURSDAY
reactions
with Jeopardy Style Review
COMPREHENSIVE FINAL EXAM:
Thursday, December 19th: 1:00-3:50 pm in 615
Grade Replacement OPTION: If you opt in, you can replace
your lowest exam grade for your final exam grade:
•
•
If you improve, this will help your overall grade by bringing
up your lowest exam grade
If you do poorly, this will hurt your overall grade
1
Concept Check
pH and Acid Strength
Which solution would have the lowest pH?
A. 0.001 M HNO3
B. 0.001 M HCl(aq)
C. 0.001 M HClO4(aq)
D. 0.001 M HBr(aq)
E. They would all have the same pH
Acid-Base Practice Problems
Write the reaction that occurs when 5.3 grams of solid Acetic
Acid (monoprotic, weak acid: CH3CO2H) dissolves in 100. mL of
water. What is the concentration of this acid in moles/L? Would
this solution be a strong electrolyte, weak electrolyte or NONelectrolyte?
2
iClicker Participation Question
pH and Acid Strength
Which solution would have the lowest pH?
A. 0.01 M CH3CO2H(aq) (Acetic Acid)
B. 0.01 M HCl(aq)
C. 0.01 M NH3(aq)
D. 0.1 M NaOH(aq)
E. They would all have the same pH
Acid-Base Practice Problems
What is the pH of a solution prepared by dissolving 5.86 grams of
barium hydroxide in water to reach a total volume of 150 mL of
aqueous solution? Would this solution be conductive?
Write the balanced equation for the reaction of aqueous barium
hydroxide with aqueous sulfuric acid.
What volume of 0.5 M sulfuric acid (H2SO4) would be needed to
fully react with the 150. mL of aqueous barium hydroxide from
above?
3
Logarithmic pH scale: pH = -log[H+]
TITRATION: A substance in solution with a known
concentration is reacted with another substance in a
solution with an unknown concentration.
• An indicator is used to signal when the reaction is complete.
• The concentration and volume of the known is then used to
calculate the moles and concentration of the unknown.
Acid Base Indicators: a dye whose color changes depending on the pH (acidity) of
the solution.
4
iClicker Participation Question
Acid-Base Titrations and Electrical Conductivity
For the titration of barium hydroxide with sulfuric acid, which
plot would best represent the change in conductivity versus
volume of sulfuric acid added?
H2SO4(aq) + Ba(OH)2(aq) → 2 H2O(l) + BaSO4(s)
A.
B.
C.
D. The conductivity would NOT change
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