Questions
1. What is the initial pH of
the solution in the Erlenmeyer flask?
2. What does this
pH tell you about the “type” of solution we
are beginning with (hint: is it an acid or base?)?
3. What ions are
present in the Erlenmeyer flask initially?
4. What ions are
present in the buret initially?
5. Draw a diagram
of the lab set-up in your notebook and label the solutions
6. Begin your virtual
titration
7. Add 5.00 mL
of NaOH
8. Does the pH
change? Explain what is happening to the ions in the Erlenmeyer
flask.
9. Now add 15.00
mL of NaOH
10. What is the
“new” pH? What is happening to the solution
in the Erlenmeyer flask?
11. Now add, 10.00
mL more of NaOH to the flask, what happens to the pH? Why
do you think there is such a change?
12. Explain why
accuracy and precision are so important when performing
titrations.
13. What is the
total volume of solution in the Erlenmeyer flask now?
14. At pH=7.00,
what ions/molecules are present in the Erlenmeyer flask?
15. Is the solution
in the flask acidic, basic, or neutral? Explain using the
terms ions and molecules in your explanation.
16. Write the reaction
for the neutralization reaction between the acid and the
base in this titration. Be sure to indicate the phases of
the ions and molecules.
17. Now add 5.00
mL more of NaOH.
18. What happens
to the pH?
19. Add 5.00 mL
of NaOH again. Does the pH change?
20. Make a sketch
of the titration curve, labeling the axes, with pH as the
dependant variable and volume of NaOH as the independent
variable.
21. What is the
net ionic equation for this reaction?
22. Why is it different
than the complete neutralization reaction?
23. Given the molarity
of NaOH and the initial volume of HCl, calculate the molarity
of the solution.
24. What is the
pH at the equivalence point?
25. What does the
pH at the equivalence point tell you about the strength
of the acid and the strength of the base?
BONUS QUESTION:
Does the equivalence
point change based on the strengths of the acids and bases
involved in the titration? Explain using graphs. |