Question

End point in conductometric titration is detected by

• A. Colour change
• B. Sharp change in conductance
• C. pH jump
• D. Potential difference

Hint:

Conductometric titration is based on measuring the electrical conductance of the solution as the titrant is added. As ions are added or removed during the reaction, the conductance of the solution changes.

Answer 1

The Correct Option is B

Concept:
Conductometric titration is based on measuring the electrical conductance of the solution as the titrant is added. As ions are added or removed during the reaction, the conductance of the solution changes. We plot conductance against the volume of titrant, and the point where the trend suddenly changes direction marks the end point.

Step 1: The name itself gives the clue — "conductometric" means we are following conductance. So the property we monitor is the conductivity of the solution, not colour, not pH, and not potential.

Step 2: Before the end point, conductance changes in one way (for example, ions being replaced by others of different mobility). After the end point, excess titrant ions cause the conductance to change in a different way. The two straight-line portions of the graph intersect, giving a sharp change that signals the end point.

Step 3: Colour change belongs to indicator titrations, pH jump belongs to acid-base potentiometric/pH titrations, and potential difference is followed in potentiometric titrations — none of these define a conductometric end point.

Answer: Option (2) — The end point is detected by a sharp change in conductance. (2)