Pharmaceutical Chemistry and Analysis Flashcards

Which spectroscopic technique measures the absorption of infrared radiation to identify functional groups in a drug molecule?

Answer: Infrared spectroscopy

Infrared spectroscopy identifies functional groups based on characteristic bond vibration frequencies in the IR region.

The Henderson-Hasselbalch equation is used to calculate which property of a drug?

Answer: Degree of ionization at a given pH

The Henderson-Hasselbalch equation relates pH, pKa, and the ratio of ionized to unionized drug forms.

Which type of isomerism occurs when two compounds have the same molecular formula but differ in the connectivity of atoms?

Answer: Constitutional isomerism

Constitutional (structural) isomers share the same molecular formula but have different atom connectivity.

In HPLC, what does the term 'resolution' describe?

Answer: The degree of separation between two adjacent peaks

Resolution quantifies how well two adjacent chromatographic peaks are separated from each other.

Which bond type is primarily responsible for the double-helix stability of DNA and is also important in drug-receptor interactions?

Answer: Hydrogen bonds

Hydrogen bonds stabilize the DNA double helix between base pairs and are critical in many drug-receptor binding events.

The optical rotation of a chiral drug is measured using which instrument?

Answer: Polarimeter

A polarimeter measures the rotation of plane-polarized light by chiral (optically active) substances.

Which reagent is commonly used in the Karl Fischer titration method for water determination in pharmaceuticals?

Answer: Iodine and sulfur dioxide

Karl Fischer titration uses iodine and sulfur dioxide (with methanol and pyridine) to react stoichiometrically with water.