Frequently Asked Question

Conductmetry is a technique used to determine the equivalence point of an acid-base titration by measuring the electrical conductivity of the solution. The equivalence point is the point at which the moles of acid added are equal to the moles of base present in the solution. At this point, the solution will have the highest conductivity, as all of the ions will be present in solution.

To perform a conductmetric titration, a conductivity meter is used to measure the conductivity of the solution as the acid is added to the base. The conductivity will initially increase as the acid is added, as the number of ions in solution increases. However, once the equivalence point is reached, the conductivity will begin to decrease as the ions start to recombine to form neutral molecules.

The equivalence point can be determined by plotting the conductivity of the solution against the volume of acid added. The equivalence point will be the point at which the conductivity is highest.

Conductmetry is a useful technique for determining the equivalence point of an acid-base titration, as it is a simple and accurate method that does not require any special reagents. The results of the titration can be used to determine the concentration of the acid or base, as well as the acid-base dissociation constant for the reaction.

Here is a more detailed explanation of the steps involved in conducting a conductmetric titration:

- Fill a burette with the acid solution.

- Add a known volume of the base solution to a beaker.

- Insert the conductivity probe into the base solution.

- Start the titration by slowly adding the acid solution to the base solution.

- Record the conductivity of the solution after each addition of acid.

- Plot the conductivity of the solution against the volume of acid added.

- The equivalence point will be the point at which the conductivity is highest.

- Determine the concentration of the acid or base using the following formula:
Molarity of acid = rac{Moles of acid}{Volume of acid (L)}

Molarity of base = rac{Moles of base}{Volume of base (L)}
- The acid-base dissociation constant can be determined using the following formula:
Ka = rac{[H+][A-]}{[HA]}
where:

- Ka is the acid-base dissociation constant

- [H+] is the molar concentration of hydrogen ions

- [A-] is the molar concentration of the conjugate base

- [HA] is the molar concentration of the acid