5.34 - Calculations from titrations Flashcards
1
Q
How do you calculate your mean titre?
A
By taking all of your concordant titres, adding them, and dividing by the number of concordant titres
2
Q
How do you calculate the unknown concentration?
A
- Calculate the number of moles of the known substance
- Use the ratio to calculate the number of moles of the other substance
- Calculate the mass of the substance
3
Q
Volume of sodium carbonate solution used = 25cm3
Volume of nitric acid solution used = 27.25cm3
Concentration of sodium carbonate solution = 0.108 mol dm-3
What is the concentration of the nitric acid?
A
Number of moles of sodium carbonate = 0.108 * (25/1000) = 0.0027 moles
Ratio = 1:2, so moles of nitric acid = 0.0054 moles
Concentration of nitric acid = 0.0054/(27.25/1000) = 0.198 mol dm-3