Standardisation of sulphuric acid using standard sodium hydroxide solution.
You will use a standard solution to find the concentration of dilute sulphuric acid by titration.
This process is known as standardising the sulphuric acid.
The reaction between sodium hydroxide and sulphuric acid is:
2NaOH(aq) + H2SO4(aq) Na2SO4 (aq) + 2H2O(l)
Goggles, 100cm3 beaker, 250cm3 beaker, 250cm3 conical flask,
25cm3 bulb pipette, Pipette filler, Burette, Burette stand and holder,
Plastic filter funnel, white tile, teat pipette
Standard sodium hydroxide solution (0.1M), dilute sulphuric acid to standardise
methyl orange indicator solution.
1. Transfer a 25cm3 aliquot (portion) of your sodium hydroxide solution to a 250cm3 conical flask. Add a few drops of methyl orange indicator solution.
2. Titrate with the sulphuric acid (in burette). The end-point of the titration is when the solution just changes from yellow/orange to red. Note the titre.
4. Repeat steps 1 - 3 until concordance (i.e. until the readings are the same or within 0.1cm3).
5. Tabulate your titrations as before.
|Burette reagent | |
|Conical flask reagent | |
|Indicator | |
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|Final volume (cm3) | | | |...