NaOH Titration Flashcards

Attitudes

• Safety
  • Wearing and closing the lab coat.
  • Ensuring glassware is clean.
  • Using materials correctly.
  • Ensuring the safety of fellow students.
  • Managing hair appropriately.
  • Managing schoolbag placement.
  • Cleaning the table and sink.
  • Paying attention to P- and H-phrases (precautionary and hazard statements).
  • Returning everything to its proper place.
  • Sorting waste.
  • Wearing safety glasses.
• Order and Cleanliness
  • Clean glassware is essential.
  • Tidy workspace is expected.
• Work Ethic/Behavior
  • Smooth collaboration is important.
  • No talking to other groups during the experiment.
• Conclusion/Reflection

Objective of the Practical

• Determine the concentration of sodium hydroxide (NaOH) through titration with a standardized hydrochloric acid (HCl) solution (0.10 mol/L).
• Learn to handle volumetric equipment: volumetric flask, pipette, pipette pump, and burette.

Orientation - Research Question

• Research Problem: Determine the concentration of NaOH by titration with a 0.10 mol/L HCl solution. The NaOH solution will be provided.

Preparation

A - Information Gathering = Preliminary Research

• Understand the principle of titration and acid-base indicators.

B - Materials Required

• Material: burette, retort stand, burette clamp, 250 mL Erlenmeyer flask, 100 mL graduated cylinder, 10 mL pipette, funnel, white card for background.
• Chemicals:
  • Phenolphthalein indicator.
  • Distilled water.
  • NaOH solution (H315-319, P280.1+3-305+351+338).
    • H315: Causes skin irritation.
    • H319: Causes serious eye irritation.
    • P280.1+3: Wear protective gloves and eye protection.
    • P305+351+338: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
  • HCl solution (0.10 mol/L) – no specific H- and P-phrases mentioned.

Execution: Procedure

• Using a pipette, transfer exactly 10 mL of the NaOH solution into an Erlenmeyer flask. Add a few drops of phenolphthalein indicator and homogenize (mix).
• Fill the burette with the 0.10 mol/L HCl solution.
• Record the initial reading of the HCl solution in the burette.
• Titrate until the solution turns colorless.
• Record the final reading of the HCl solution in the burette.
• Perform the titration at least three times and calculate the average volume of HCl added.
• Empty the burette and rinse it thoroughly with tap water.
• Experimental setup: Drawing of the setup is required, labeling all parts.

Measurement data

• Record the following data for each titration:
  • Initial burette reading (mL).
  • Final burette reading (mL).
  • Volume of 0.10 mol/L HCl added (mL).
• Calculate the average volume of HCl added.

Calculations

• Calculate the concentration of NaOH in the solution, expressed in mol/L.
• Calculate the concentration of NaOH in the solution, expressed in m/V% (mass/volume percentage).

Reporting - Reflection

Evaluating Execution

• Does the calculated concentration match the value on the label? If not, what could be the reasons for the discrepancy?