JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Pharmacy I Year PHARMACEUTICAL ANALYSIS-I Previous Question Paper (June-2022 - R17)

Pharmaceutical analysis involves various techniques categorized based on the physical or chemical properties of the analyte:

1. Volumetric Analysis (Titrimetric): Measures the volume of a standard solution required to react completely with the analyte. Examples include acid-base, redox, precipitation, and complexometric titrations.
2. Gravimetric Analysis: Involves the isolation and weighing of a pure substance, usually in the form of a precipitate, to determine the quantity of the analyte.
3. Spectroscopic Methods: Based on the interaction of electromagnetic radiation with matter. Common techniques include UV-Visible, IR, and Atomic Absorption Spectroscopy.
4. Chromatographic Methods: Used for the separation and identification of components in a mixture based on differential distribution between stationary and mobile phases (e.g., HPLC, GC, TLC).
5. Electrochemical Methods: Based on electrical measurements such as potential (potentiometry), current (amperometry), or conductivity (conductometry).

Primary Standards: These are highly pure chemical substances used to prepare standard solutions whose concentration is known precisely by direct weighing. A primary standard must meet specific criteria: high purity, stability in air, absence of hydrate water, ready availability, and a high equivalent weight to minimize weighing errors. Examples include potassium hydrogen phthalate, sodium carbonate, and sodium chloride.

Secondary Standards: These are substances whose concentration cannot be determined by direct weighing because they are not pure enough, are hygroscopic, or are unstable. Their concentration must be determined by standardization against a primary standard. Examples include sodium hydroxide (which absorbs CO2 and moisture) and potassium permanganate (which is not perfectly stable).