Experiment 14: TO DETECT THE ACID RADICAL PRESENT IN GIVEN INORGANIC SALT
OBJECTIVE
TO DETECT THE ACID RADICAL PRESENT IN GIVEN INORGANIC SALT (S1) BY WET WAYS METHOD
APPARATUS REQUIRED
- Test tube
- Test tube holder
- Test tube stand
CHEMICALS REQUIRED
- AgNO3
- BaCl2
- HNO3
THEORY
Qualitative inorganic analysis is concerned with detecting and identifying radicals present in inorganic salt or a mixture of salts. Inorganic salts are the outcome of the neutralization of acids with base. Each inorganic salt consists of two parts. The part contributed by acid is called acid radical or anion and the part contributed by base is called basic radical or cation. For example, in sodium chloride, which can be obtained by the neutralization of base NaOH with acid HCl, Na+ is the basic radical and Cl- is the acid radical.
PROCEDURE
The original solution was prepared by dissolving the given salt sample in water. The sample was subjected to several tests for the detection of acid radicals in the salt.
PHYSICAL PROPERTIES
- State: Crystalline solid
- Colour: White
- Odour: Odourless
- Solubility: Soluble in water
OBSERVATION TABLE
Experiment | Observation | Inference |
1. AgNO3 test: 2 ml of the original solution was taken in a clean and dry test tube which was acidified with dilute nitric acid and a few drops of AgNO3 the solution was added to it. | Curdy white ppt. was obtained which was soluble in ammonium hydroxide solution and reappeared with the addition of nitric acid. | Presence of Cl– |
2. BaCl2 test: 2 ml of the original solution was taken in a clean and dry test tube and a few drops of barium chloride solution was added to it. | White ppt. was not formed. | Absence of SO4– –or CO3– – |
3. Ring test: 2 ml of the original solution was taken in a clean and dry test tube and double the volume of conc. H2SO4 was added. The content was cooled and freshly prepared FeSO4 was added through the walls of the test tube and was allowed to stand for some time. | The brown ring was not formed | Absence of NO3– |
Reactions involved
Cl^{-}+AgNO_{3}\rightarrow \underset{white\ ppt.}{AgCl}+NO_{3}^{-}

RESULT
The acid radical present in the given inorganic salt was found to be Cl– (chloride ion).
CONCLUSION
We can detect the acid radical present in given inorganic salt by wet ways.
PRECAUTION
- Salt solution should be used in small amounts.
- The salt solution should not be too concentrated.
- The test tube should be clean and dry.