Chapter 1 – Chemical Analysis
Qualitative Analysis
• Analysing what is present in the substance.
• It can also give information about the
structure of newly discovered compounds
such as potential new drugs.
Quantitative Analysis
• The analysis to find the amount of each
chemical is present.
Analytical Techniques
• The most appropriate chemical technique to use
depends on factors including, the nature of the
sample, the nature of the chemical under
analysis, the concentration of the chemical, the
accuracy required, the time available and the cost
and benefits in carrying out that specific
technique.
• Many different chemical and physical properties
can be used as a basis for qualitative analysis.
• These properties are then compared with the
properties of known substances.
Technique
Physical or Chemical Property
Examples of Analysis
Mass of chemical, isolated from a mixture or
precipitated in a reaction
Percentage of water in wheat stored in a silo.
Concentration of salt in a jar of baby food
Acid-Base Titrations
Neutralisations reactions by acid or base
Concentration of ammonia in window cleaner
Redox Titration
Reactant as an oxidant or reductant
Concentration of hydrogen peroxide in hair
bleach.
Chromatographic Analysis
- Paper
- Thin Layer
- Gas
- High Performance Liquid
Adsorption onto a stationary phase and
solubility in a mobile phase
Analysis of codeine in a tablet
Concentration of alcohol in the blood
Spectroscopic Analysis
-Flame Tests
-Atomic Emission
-Atomic Absorption
-Ultraviolet-Visible
-Infrared
-Nuclear Magnetic Resonance
Absorption or emission of part of the
electromagnetic spectrum
Monitoring level of calcium in the blood
Mass Spectrometry
Mass/charge ratio of ionised compound
Identification of lead isotope ratios in meteors
Analysis by Mass
Gravimetric Analysis
Volumetric Analysis