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• What is the first step in making a volumetric solution?

  Calculate the mass of required substance.
• How do you ensure the balance reads zero before weighing?

  Place the weighing bottle and zero the balance.
• Why is it important to record all weighings accurately?

  To ensure precision in the mass measurement.
• What does 'weighing by difference' involve?

  Calculating the mass transferred by subtracting values.
• What should you do if the solid does not dissolve well in cold water?

  Gently heat the beaker until dissolved.
• Why is it necessary to wash the beaker and funnel during transfer?

  To minimize loss of solution during transfer.
• How do you ensure the volumetric flask is filled accurately?

  Fill until the meniscus is at the mark.
• What is the purpose of inverting the volumetric flask?

  To mix the contents thoroughly for uniformity.
• What is the first step in the titration method?

  Pour standard solution into a beaker.
• Why is it important to rinse the burette before use?

  To ensure accurate measurement of the solution.
• What should you do to avoid air bubbles in the burette?

  Fill the jet space to eliminate air bubbles.
• How much of the unknown solution is transferred to the conical flask?

  25 cm​3​ of the solution.
• Why is a conical flask preferred over a beaker for titration?

  It allows easier swirling without spills.
• What is the effect of adding too much phenolphthalein indicator?

  It can affect the titration result.
• What should be recorded after the initial burette reading?

  Final burette reading after titration.
• Why is distilled water used during titration?

  It does not change the number of moles.
• How many titrations should be performed for accurate results?

  At least three titrations should be done.
• What indicates that titration results are concordant?

  Two or three values within 0.10 cm​3​.
• What should be done with titre volumes in results?

  Record to 2 decimal places (0.05 cm​3​).
• What safety precautions should be taken during titration?

  Wear eye protection and gloves.
• What should be considered when titrating a mixture?

  Presence of other acid-base substances.
• Why is it necessary to test several samples in quality control?

  Concentration may vary between samples.
• What is the uncertainty of a burette reading?

  +/- 0.05 cm​3​ for each reading.
• How can you reduce uncertainty in a titration?

  Use pipettes or burettes for measurement.
• What happens if NaOH is left in the burette?

  It can damage the apparatus and cause errors.