Question

To determine strenghth of hcl using naoh conductometrically

Answer 1

The titration curve obtained is not exactly straight line as per my understanding but a V shaped curve is obtained.

When a solution of NaOH is added from a burrette, after each definite volume of the base the conductance decreases initially as number of H+ ions decreases beacuse of the reaction H+and OH- leading to formation of water the place of H+ ions is taken by slower moving Na+ ions and consequently the conductance decreases progressively.The decrease in conductance continues till the end point of titration. At the end point the concentration of H+ ions is negligible, beyond this point on adding NaOH the excess of OH- ions of added NaOH increases the conductance sharply. Thus plotting the conductance against the volume of NaOH added, a v shaped graph is obtained. The minimum point in the graph denotes end point. Please refer the attached picture.