Neutralisation

• What is a titration used for in chemistry?

  To determine the concentration of an unknown solution
• What two solutions are involved in the titration described?

  Sodium hydroxide and sulfuric acid
• What is the known concentration of sodium hydroxide used?

  0.1 mol per decimeter cubed
• What is the approximate concentration of sulfuric acid?

  0.05 mol per decimeter cubed
• What equipment is used to measure an exact volume of solution?

  A pipette
• What type of pipette is used in this experiment?

  A bulb pipette
• Why can't we suck the solution into the pipette using our mouths?

  Health and safety concerns with sodium hydroxide
• How do we attach the safety filler to the pipette?

  Hold the top and twist it on firmly
• What is the purpose of the meniscus in the pipette?

  To indicate the exact liquid level
• How do you ensure the liquid level is at the correct mark?

  Bring it to eye level and adjust
• What should you do with the last drops in the pipette?

  Let them drip out, do not blow them out
• What is the purpose of the burette in this experiment?

  To measure the volume of sulfuric acid
• How do you fill the burette safely?

  Fill it below eye level and ensure the tap is closed
• What indicator is used in this titration?

  Methyl orange
• What color indicates the presence of sodium hydroxide with methyl orange?

  Yellow
• What indicates the endpoint of the titration?

  A permanent pink color change
• How do you perform a rough titration?

  Add acid quickly and look for color change
• Why is it important to perform accurate titrations after the rough one?

  To obtain reliable and precise results
• What should you do if you overshoot the endpoint?

  Repeat the titration for accuracy
• What is the balanced equation for the reaction?

  2 NaOH + H2SO4 → Na2SO4 + 2 H2O
• How do you calculate moles from concentration and volume?

  Moles = concentration × volume
• How do you convert volume from centimeters cubed to decimeters cubed?

  Divide by 1000
• What is the mole ratio between sodium hydroxide and sulfuric acid?

  2 moles of NaOH to 1 mole of H2SO4
• How do you find the concentration of sulfuric acid after titration?

  Concentration = moles / volume
• What was the final calculated concentration of sulfuric acid?

  0.095 mol per decimeter cubed
• How does the final concentration compare to the initial estimate?

  It is nearly twice as strong