Question

3. The endpoint of a titration involving the reaction of MnO4- to Mn2+ can be detected
by the ... *

A) useofa pH probe.
B) use of redor blue litmus.
C)pink colour of the Mn+2.
D)addition of an indicator like methyl orange.

Answer 1

The solution of manganese ion, Mn2+ is colorless. This way, the reaction involves a colour change from pink to transparent.

There is no option with this information.

So, the best answer is (A)

Answer 2

Answer:

C)pink colour of the Mn+2.

Explanation:

First of all, a titration involving the change from MnO4- to Mn2+ is a redox reaction.

This redox reaction does not need an indicator because the MnO4- has a deep violet colour while Mn2+ has a light pink colour.

Hence, the change from MnO4- to Mn2+ is signaled by the appearance of the light pink colour of Mn2+ at end point.