DIGITAL TITRATION OF ACIDS AND BASES LAB
SIMULATION EXAM WITH CALCULATIONS AND
PRACTICAL QUESTIONS AND CORRECT ANSWERS
Instructions
• Read each question carefully before answering.
• Show all calculations with proper units and significant figures.
• Use the data provided in each section.
• Assume standard laboratory conditions unless otherwise stated.
• Total Marks: 100
• Time Allowed: 2 Hours
Section A – Multiple Choice Questions (20 Marks)
Choose the best answer for each question.
1. What is the primary purpose of an acid-base titration? A. To determine the melting
point of a compound B. To determine the concentration of an unknown solution C.
To identify a precipitate D. To measure electrical conductivity
2. In a titration, the solution of known concentration is called the: A. Analyte B. Solvent
C. Titrant D. Indicator
3. Which indicator is commonly used for strong acid–strong base titrations? A. Methyl
orange B. Phenolphthalein C. Bromothymol blue D. Litmus
4. At the equivalence point of a strong acid–strong base titration, the pH is
approximately: A. 2 B. 5 C. 7 D. 10
5. Which laboratory instrument is used to deliver precise volumes of titrant? A. Beaker
B. Volumetric flask C. Pipette D. Burette
6. A sudden permanent color change during titration indicates the: A. Initial point B.
Neutralization point C. Endpoint D. Saturation point
7. If too much indicator is added during a titration, it may: A. Improve accuracy B.
Change the pH significantly C. Increase reaction speed D. Prevent neutralization
, 8. Which acid is considered a strong acid? A. Acetic acid B. Carbonic acid C.
Hydrochloric acid D. Citric acid
9. During a digital titration simulation, the pH meter should be: A. Left dry B. Calibrated
before use C. Heated before use D. Connected after titration
10. What is the formula used to calculate molarity? A. M = mass × volume B. M = moles
÷ liters C. M = liters ÷ moles D. M = density ÷ volume
Section B – Short Answer Questions (30 Marks)
11. Define the following terms:
a. Acid
b. Base
c. Endpoint
d. Equivalence point
12. Explain why rinsing the burette with distilled water only may affect titration
accuracy.
13. Describe the role of an indicator in acid-base titration.
14. State two differences between strong acids and weak acids.
15. Why is it important to remove air bubbles from the burette tip before beginning a
titration?
16. In Beyond Labz, what steps are followed to prepare a digital titration setup?
17. Explain how a pH curve changes during a strong acid–strong base titration.
18. List three possible sources of experimental error in a titration experiment.
Section C – Calculations and Data Analysis (30 Marks)
Question 19
A student titrates 25.00 mL of HCl with 0.100 M NaOH. The endpoint occurs after 18.60 mL
of NaOH is added.
Calculate:
a. The number of moles of NaOH used.
b. The number of moles of HCl present.