J.R. S. answered • 11/07/20
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You can do it mathematically. The equivalence point is when the moles of the analyte and titrant are present in stoichiometric equivalent amounts.
Examples:
HCl + NaOH, ... when moles of HCl = moles NaOH
H2SO4 + 2 NaOH ... when moles of H2SO4 = 2 x moles NaOH
H3PO4 + 3 NaOH ... when moles of H3PO4 = 3 x moles NaOH
If this is not a satisfactory explanation, let me know and I'll try to further clarify.
Lily P.
Thanks for your answer. The problem is I do not know the concentration of HCl to know the moles. It is what I will calculate through my drawn titration curve. The first thing I need to know is when the equivalence point is reached, so I can read the volume of NaOH added to HCl. From that, I get the moles of added NaOH which is then equal to moles HCl available in the beginning. Knowing the volume of HCl I had, I could use that to calculate the concentration asked. However, I am not sure where the equivalence point could be found exactly. I know that theoretically, it is by pH= 7, but I do not want to assume that as the curve is based on a practical experiment which could have some error sources.11/08/20