Page 37 - Chemistry - XI

Titrimetric
5 Titrimetric ( Volumetric )( Volumetric )
Analysis
Analysis

Volumetric Analysis
Volumetric analysis is a method in quantitative chemical analysis in which the amount of a substance is
determined by the measurement of the volume that the substance occupied. It is used to determine the
unknown concentration of a known reactant. Usually the concentration terms are normality and molarity.

Terms Used in Volumetric Analysis
1. Titration is a process of adding a solution carefully from the burette into another solution taken in the
conical fl ask till the chemical reaction between them is just complete.
2. Titrant is a solution of known strength and is usually taken in the burette.

3. End Point or Equivalence Point represents a stage when the chemical reaction involved in the titration
is just complete.
4. Indicator is a substance which indicates the completion (end point) of a titration (by change of colour).
5. Strength is a way to express the concentration. It may be expressed in W/V, E/V (normality) or M/V
(Molarity). W/V is the amount of a substance present per litre of the solution. It is known as strength

of the solution and expressed in grams/litre (g L ).
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6. Normality is the number of gram equivalents of the solute present per litre of the solution. It is
represented by N.

Normality Weight of substance in grams 1000
Equivalent weight of substanceVolume of solution in mL

or Normality (N) of a solution Strength of solution in g L 11
Equivalent weight of the solute

Strenght of solution Normality of thesolution Eqwt. . oof thesolute

7. Normal solution: A solution which contains 1 g eq. of the solute in one litre of the solution is called a
normal solution. It is represented as 1 N.
8. Molarity is the number of moles of the solute present per litre of the solution. It is represented by M.

A solution which contains 1 mole of the solute in 1L of the solution is referred to as one molar (1M)
solution.

Molarity Weight of substance in grams 1 1000
Molecularmassof substance Volume of solutioninmL

or Molarity (M) of a solution Strength of solution in g L 1
M Molecularmassofthe solute

Strengthofsolution Molarity of thesolution Molecularmass oof thesolutethesolutees
es
th
th

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