| OBSERVATIONS |
1. Preparation of 250 mL M/80 standard Na2CO3 solution
|
Mass, w of Na2CO3 to be weighed for the preparation of solution |
w = 1 x 106 x 250 = 0.3312 g
80 x 1000
|
|
| Mass of empty weighing bottle = X = |
|
| Mass of weighing bottle and Na2CO3 = Y = |
|
| Mass of weighing bottle after transfer = Z = |
|
| Actual mass of Na2CO3 transfer = w1 = (y-z) = |
0.0000 g |
2. Titration of standard Na2CO3 solution against HCl
|
| Solution in burette = HCl | |
| Solution in titrating flask = V1= 20 mL standard Na2CO3 | |
| Indicator used = methyl orange | |
| End point = yellow to orange | |
|
| S.No. |
Burette reading |
Volume of HCl used |
| Initial |
Final |
| 1 |
|
|
|
| 2 |
|
|
|
| 3 |
|
|
|
| Concordant volume (V2) : |
mL |
3. Titration of given Na2CO3 solution against HCl solution.
|
| Solution in burette = HCl | |
|
Solution in titrating flask = V3=20 mL of given Na2CO3 solution |
|
| Indicator used = methyl orange | |
| End point = yellow to orange | |
|
| S.No. |
Burette reading |
Volume of HCl used |
| Initial |
Final |
| 1 |
|
|
|
| 2 |
|
|
|
| 3 |
|
|
|
| Concordant volume (V4) : |
mL |
| CALCULATIONS |
| 1. Molarity of standard Na2CO3 solution: |
| M1 = |
w1 x 1000/(molar mass x V) |
| M1 = |
0.0000 x 1000/106 x 250 |
| M1 |
0.0000 M |
| 2. Molarity of given HCl solution: |
| M1 V1 / n1 = |
M1 V1 / n1 |
(Standard Na2CO3)
n1 = 1; |
(HCl)
n2 = 2 |
| M2 = |
M1 x V1 x n2
V2 x n1
|
| M2 = |
M |
| 3. Molarity of given Na2CO3 solution |
| M3 V3 x 2 = |
M2 V4 x 1 |
| (Given Na2CO3) |
(HCl) |
| M3 = |
M2 x V4
2v3
|
| M3 = |
M |
| Strength of the given Na2CO3 will therefore be = M3 x 106 =
|
| RESULT |
| The Strength of given Na2CO3 solution is =
g L-1 |
|
|
