Aqueous and Non-Aqueous titration

An analytical technique that measures the concentration of a definite chemical solution is known as titration. Specific apparatus is used for the process of titration. This process requires some specific apparatus or materials, that are – burette, beaker, standard solution, sample, indicator, or pipette. This process is processed as firstly we put standard solution or we can say titrant in burette ( titration flask), and sucked required amount of sample (analyte) through a pipette and put it into a beaker or conical flask than a place that flask or beaker below the burette and at last start dropping titrant drop by drop in a sample, till the reaction is finished. When the colour changes it is declared as the terminus. A few drops of the indicator are added to the sample which causes a colour change. There are four different types or forms of titration such as acid-base titration, redox titration, complexometric titration and precipitation titration. 

Types of titration:-

Acid-base titration:- 

An acid-base titration is also known as neutralisation titration.By utilising base/acid in a burette and liquefying an unknown sample in the water we can find out the amount of acid/base in the sample.After the complete process of titration, the solution is neutral and can have a 7.0 pH.

Redox titration:-

Redox titration is an oxidation-reduction reaction. To find out the sum of the craved substance in the sample, the reducing agent will proceed with the oxidising agent.This sample is in the State of aqueous because we want to liquefy it in water.

Complexometric titration:-

In this titration formation of complex molecules takes place at the climax of the titration process.This reaction is categorised under aqueous titration because a chemical reaction occurs in an aqueous solution.

Precipitation titration:- 

In precipitation titration, a solid precipitate forms at the base of the flask which is used for the titration process. In this titration, the analyte (sample) should be in an aqueous form, and the formed precipitate would not be soluble in water.

Aqueous titration:- 

Aqueous titration refers to the process of titration that executes in an aqueous solution ( solution of water). Aqueous titration is the titration process which utilises water in place of sample solvent for the determination of the concentration of solute in the sample. In analytical chemistry, some aqueous titrations are used – Aqueous Acid-base titration, aqueous redox titration,  precipitation titration, and complexometric titration. 

Non-aqueous titration:- 

 “Non-aqueous titration” means water less solvent. This titration is useful for titration of very weak acids and weak bases where water can not be used. In this process, the solute is titrated with an acid or base titrant. The non-aqueous titration principle is the same as the principle of acid-base titration which is the Bronsted-lowry theory. According to this principle, acid can donate a proton to a substance that accepts it called the base. Four types of solvent utilised in non-aqueous titration are –  

• Aprotic solvent:- these solvent are the inert solvent, not either acidic or basic.
• Protophilic solvent:- these are those solvent which has the ability to accept protons.
• Protogenic solvent:- these are those solvents which generate protons. 
• Amphiprotic solvent:-  these solvent shows the properties of both protophilic solvent and protogenic solvent.

There are also some types of non-aqueous titration such as non- aqueous acid-base titration, non- aqueous redox titration, iodometry and iodimetry. The chemical reaction occurs in an organic solvent in this titration process. 

Difference between aqueous and non-aqueous titration-

• Aqueous titration and non-aqueous titration both are considered as  analytical techniques. And the main difference between aqueous titration and the non-aqueous titration is that aqueous titration utilises water as a solvent to liquefy in analytes samples whereas non-aqueous titration utilises organic solvent for liquification of the sample.

• Types of aqueous titration are- acid-base titration, aqueous redox titration, complexometric titration and precipitation titration whereas the types of non-aqueous titration are acid-base titration, non-aqueous redox titration, iodimetry and iodometry.

• Sometimes, in aqueous titration precipitate formed at the base of the flask whereas in non-aqueous titration no precipitate formed.

• Examples of aqueous titration are the solution of common salt and the solution of sugar in water. An example of non-aqueous titration is sulphur disulphide in carbon disulphide.

• Litmus ( azolitmin) is used as an indicator in aqueous titration and non-aqueous titration crystal violet is used as an Indicator.

Conclusion:- 

Titration is considered an analytical technique which is used to compute the amount of craved substance present in a sample. The aqueous titration can be defined as the process of titration that executes in an aqueous solution (where aqueous solution means solution of water). Non-aqueous titration can be defined as the process in which solute liquefies in a non-water containing solvent. Aqueous titration and non-aqueous titration are analytical techniques and the main difference between aqueous and non-aqueous titration is that aqueous titration utilises water as a solvent and non-aqueous titration utilises organic solvent. There are also some other differences between aqueous and non-aqueous titration, as aqueous titration types are- acid-base titration, aqueous redox titration, complexometric titration and precipitation titration whereas the types of non-aqueous titration are acid-base titration, non-aqueous redox titration, iodometry and iodimetry. Different indicators are used in both titration processes, in aqueous titration litmus is used as an indicator and in non-aqueous titration, crystal violet is used as an indicator.