5

ESTIMATION OF DISSOLVED OXYGEN IN THE GIVEN WATER SAMPLE

AIM

To estimate the amount of dissolved oxygen present in the given water sample.

METHOD

Winkler’s method.

PRINCIPLE

The given sample is treated with manganous sulphate followed by alkaline iodide. First, manganous sulphate reacts with potassium hydroxide resulting in potassium sulphate and manganous hydroxide.

uEquation14a.png

Manganous hydroxide thus formed reacts with the dissolved oxygen present in the sample and forms manganic hydroxide.

uEquation14b.png

Manganic hydroxide thus formed reacts with potassium iodide in ...

Get Engineering Chemistry now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.