Assessed Practical Titration Write-Up

564 Words2 Pages

Assessed Practical Titration Write-Up

Equation:

Na2CO3 + H2SO4 à Na2SO4 + CO2 + H2O

One mol of Na2CO3 reacts with one mol of H2SO4.

Results:

The weight of my sodium carbonate crystals was 2.67g and the results

of the titrations are as follows:

Rough

1st

2nd

3rd

4th

5th

6th

Initial Reading

00.00

00.50

00.00

00.00

00.00

00.00

00.20

Final Reading

26.45

26.45

26.05

27.00

25.85

25.90

26.10

Titration

26.45

25.95

26.05

27.00

25.85

25.90

25.90

pH

slightly acidic

neutral

slightly acidic

slightly acidic

slightly alkali

neutral

neutral

So the average of the closest three titration results are is:

25.95 + 25.90 + 25.90 / 3 = 25.92

The mass of Na2CO3 I used is 2.67g and the relative molecular mass of

Na2CO3 is 106. So the number of mols of Na2CO3 I used was:

2.67 / 106 = 0.0251 mols in 250 cm3

So the concentration of the Na2CO3 solution was: 0.1004 mol dm-3.

So in the 25cm3 of Na2CO3 solution I used, there were:

0.0251 / 10 = 0.00251 mols.

The equation shows how 1 mol of Na2CO3 reacts with 1 mol of H2SO4, so

0.00251 mols of Na2CO3 reacts with 0.00251 mol of H2SO4. So in the

25.92 cm3 of acid I reacted with the Na2CO3 solution, there are

0.00251 mols. So the concentration of the acid is:

( 0.00251 / 25.92 ) x 1000 = 0.0968 mol dm-3

So the concentration of the acid is 0.0968 mol dm-3.

Evaluation:

There may have been some limiting factors during the experiment which

may have affected the results. The first of these may have been the

scales, it is possible that when I was weighing out my Na2CO3

Open Document