iodimetric titration pdf

1. What is the difference between iodometric and Iodimetric titration?
2. What is the principle of iodometric titration?
3. What is meant by iodometric titration?
4. What do you mean by Iodimetry?
5. Which indicator is used in iodometric titration?
6. Why is iodine kept in the dark?
7. Why we add H2SO4 in iodometric titration?
8. Why sodium bicarbonate is added in iodometric titration?
9. Why starch is used as indicator?
10. How do you use starch indicator?
11. What is back titration?
12. Why iodometric titrations are done in dark?

What is the difference between iodometric and Iodimetric titration?

In iodimetry, a species is directly titrated with an iodine solution, but in iodometry a species is titrated with an iodide solution and then the released iodine is titrated with thiosulphate. ... Iodometry can be used to quantify oxidizing agents, whereas iodimetry can be used to quantify reducing agents.

What is the principle of iodometric titration?

The Basic Principle of iodometric titration is to determine the concentration of an oxidising agent in solution. iodometry involves indirect titration of iodine liberated by reaction with the analyte.In an iodometric titration, a starch solution is used as an indicator since it can absorb the I2 that is released.

What is meant by iodometric titration?

Iodometry, known as iodometric titration, is a method of volumetric chemical analysis, a redox titration where the appearance or disappearance of elementary iodine indicates the end point. ... The iodometric titration is a general method to determine the concentration of an oxidising agent in solution.

What do you mean by Iodimetry?

Volumetric analysis involving either titration with a standardized solution of iodine, or the release by a substance under examination of iodine in soluble form, so that its concentration can be determined by titration, using starch as an indicator.

Which indicator is used in iodometric titration?

The indicator that is usually chosen for titrations involving iodine (triiodide) is starch. Starch forms a dark blue complex with iodine. The end point in iodimetry corresponds to a sudden color change to blue. Likewise the end point in iodometry corresponds to a sudden loss of blue color due to the complex.

Why is iodine kept in the dark?

In presence of light Iodine solution undergoes a photo-decomposition reaction so it must be stored in a dark bottle , generally in amber bottle to minimize the amount of light that the solution is exposed to.

Why we add H2SO4 in iodometric titration?

Sulphuric Acid (H2SO4) is used in the redox titration process because it provides the H(+) ions necessary for the reaction to occur more quickly whilst the sulphate(-) ions barely react during the reaction. ... Therefore, sulfuric acid is added to make the solution acidic.

Why sodium bicarbonate is added in iodometric titration?

Sodium thiosulfate the usual titrant used for iodometric titrations. ... To keep the thiosulfate solution stable, NaHCO3 , which is a weak base helps to keep the solution slightly alkaline to slow down the decomposition of thiosulfate.

Why starch is used as indicator?

Starch is a viable indicator in the titration process because it turns deep dark blue when iodine is present in a solution. When starch is heated in water, decomposition occurs and beta-amylose is produced. Beta-amylose combines with iodine, resulting in a dark blue color change.

How do you use starch indicator?

To prepare starch indicator solution, add 1 gram of starch (either corn or potato) into 10 mL of distilled water, shake well, and pour into 100 mL of boiling, distilled water. Stir thoroughly and boil for a 1 minute. Leave to cool down. If the precipitate forms, decant the supernatant and use as the indicator solution.

What is back titration?

Back titration is a titration done in reverse; instead of titrating the original sample, a known excess of standard reagent is added to the solution, and the excess is titrated.

Why iodometric titrations are done in dark?

The reaction mixture should be kept in the dark before titration because light accelerates a side reaction in which iodide ions are oxidized to iodine by atmospheric oxygen.