redox titrations - unit 4 AOS 2

Question 1

titration

Answer 1

• quantitative technique used to find the concentration and/or amount of substance in a solution
• The basic principle of titration is that by reacting a solution of known concentration with a solution of
  unknown concentration, chemists can use their understanding of volume-volume stoichiometry to calculate the concentration of the unknown solution.

Question 2

titration set up

Answer 2

• To prepare a titration experiment, a pipette is used to transfer a known volume, called an aliquot, of a sample solution of unknown concentration (analyte) into the conical flask, along with the relevant indicator.
• The conical flask is placed under the
  burette, and the burette is usually then filled with a solution of known concentration.
• This solution is dispensed incrementally from the burette into the conical flask, resulting in a chemical reaction in the conical flask.

Question 3

concordant titres

Answer 3

• The experiment is repeated multiple times until concordant titres (usually all titres within ± 0.1 mL) are obtained to increase the reliability and precision of the results by minimising the effects of random errors.

Question 4

titration experimental errors

Answer 4

• use the average titre to calculate the mol of known substance from the burette (use n=cv)
• compare the mole ratio of the known and unknown substance
• use this ration to find the mole of the known substance
• apply dilution factors
• calculate the concertation of the unknown substance (use c=n/v)

Question 5

degree of unsaturation of fats and oils