Volumetric analysis
exercise 9
4.00g of an unknown triprotic acid was placed in a volumetric flask and made up to 250ml of solution. A 20ml aliquot was taken and titrated against a 0.109M NaOH solution. The result is shown on the right
Calculate the relative molecular mass of the acid
|
Volume
|
|
| Start |
15.40
mls
|
| Finish |
32.22
mls
|
| Total |
The equation for the reaction is shown below.
Step 1 Calculate
the mole of sodium hydroxide
Mole = volume X concentration
Step 2 Using the equation calculate the number of mole of acid required to react completely
Step 3 Find
the molecular mass of acid
Molecular mass = mass
/ mole