Titrations and titration calculations

Question 1

how do you complete an accurate acid-base titration?

Answer 1

1. wash the burette and pipette with a small amount of the solution that will be used for the experiment
2. check there is no air in the jet when burette is filled
3. remove the funnel, then check the reading
4. fill pipette so the bottom of the meniscus is on the line
5. touch surface of solution with tip of pipette to remove last drop
6. add a few drops of indicator
7. swirl the flask as solution is added from burette, the first run is a trial to see the rough volume needed
8. after reading of conical flask, rinse with deionised water
9. repeat to achieve concordant results (within 0.1)
10. go dropwise near the end point
11. white tile below conical flask
12. eye level when reading the meniscus

Question 2

what should you remember when recording titration results?

Answer 2

• do a table with both horizontal and vertical lines
• every burette reading must be to 2 decimal places
• include units for all rows of the table
• ensure all calculations are correct
• achieve at least two concordant titres

Question 3

what are the 4 stages for titration calculations?

Answer 3

1. write the balanced equation
2. start with the substance you are told about, calc number of mols used (n = c x v)
3. look at the equation for the ratio with the substance asked about, work out no. of mols of this substance
4. convert from moles to what you are asked about in Q, e.g conc (c = n/v)

Question 4

With an acid-base titration which goes in the burette?

Answer 4

Burette = acid
Flask = base