Volumetric analysis
exercise 7
|
Volume
|
|
| Start |
15.40
mls
|
| Finish |
32.22
mls
|
| Total |
A 0.150gram sample of hydrated sodium carbonate was dissolved in 20 mls of water. The solution was then titrated against a 0.2M HCl solution. The result is shown on the left.
What mass of the sample is due to water?
( Atomic mass of Na = 23, H = 1, O =16, C =12)
The equation for the reaction is shown below.
Step 1 Calculate
the mole of substance delivered from the burette. In this case HCl solution.
Mole = Average Volume(litres)
X Concentration
Step 2 Using the equation calculate the number of mole of sodium carbonate in the sample.
Step 3 Find
the mass of sodium carbonate present in the sample.
Step 4 Calculate the mass of water in the sample.