Question

In complex formation potentiometric titration with EDTA solution, the working electrode is La and the reference electrode is saturated calomel.

This is the table of titration 25 ml ionic solution La³⁺ with EDTA solution 3,95x10^-3 M. Determine the concentration of La³⁺.

Vol EDTA (mL) 0,00 0,02 0,04 0,06 0,08 0,10 131,5 129,0 124,0 113,5 103,5 101,0 100,0 99.0 0.14 0.16 0,18 0,20 98,0 98,0 97,0 96,0 95.5 95.0 0,30 0,35 0.40

Answer 1

1 Volume of EDTA(mL) EMF(mV) 131.5 129 124 113.5 103.5 101 100 0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2 0.25 0.3 0.35 0.4 Potentometric Titration 140 120 100 E 80 End Point(0.6,113.5) 98 98 98 97 96 95.5 95 01 40 20 0 0 0.1 0.3 04 lof EDTA(mL) 6