Introduction to Chemical Analysis
The process of determining chemical identities of the constituents of a sample is known as chemical analysis. Chemical testing and analysis are essential to understand the quality and composition of chemical substances and to follow regulatory compliance for industrial products and processes. Chemical testing and analysis services include substance composition analysis, trace contamination detection, metals testing, identification of unknown components in sample, purity detection, and regulatory testing.
Chemical composition analysis is required across various industries such as specialty chemicals, pharmaceuticals, nanomaterials, agrochemicals, petrochemicals, dyes & detergents, pesticides & insecticides, automotive, and other consumer products.
Qualitative Analysis
This deals with the identification of elements and groups of elements (functional groups) in a material sample. The result is non-numerical information about all the elements and/or functional groups present in the sample. This method utilizes wet chemistry techniques i.e., using various chemical reactions and visually distinct results indicating a particular information.
Qualitative analysis is of two types, inorganic and organic qualitative analyses. Inorganic analysis determines the elemental and ionic composition of a sample, usually by examination of ions in aqueous solution. Organic analysis tends to look at types of molecules, functional groups, and chemical bonds e.g., iodine test for starch.
Qualitative analysis measures changes in color, odor, bubble production, precipitation, melting point, boiling point, reactivity, and radioactivity. Distillation, extraction, precipitation, chromatography, and spectroscopy are the common methodologies used for qualitative chemical analysis. The common examples include flame test (inorganic materials), iodine test for starch, detection of metallic ions, detection of halide ions etc.
Quantitative Analysis
This deals with the quantitative determination of components (elements and/or functional groups) present in a material sample. The stoichiometry of chemical reactions serves as the basis for quantitative chemical analysis methods such as titration, gravimetric analysis, and combustion analysis used commonly for quantitative analysis.
Quantitative analysis uses various analytical techniques and instruments. The major techniques used are mass spectrometry, liquid & gas chromatography, estimation of organic compounds by Liebig/Duma’s/ Kjeldahl’s method/Carius method etc.
Important Applications of Chemical Analysis
- Chemical Composition Analysis – A combination of techniques is utilized to determine chemical quality, identity, composition and impurities in a sample along with the sample’s molecular structure elucidation and chemical structure confirmation.
- Chemical Trace Analysis – This includes analysis, detection and identification of impurities present in very low quantities i.e., traces, in a sample. Usually metals are present in trace quantities in organic samples and are difficult to analyze by the normal methods. This also involves study of extractables and leachables to quantify potential leachable impurities originating from pharmaceutical containers, process equipment, and medical device packaging.
- Elemental Analysis – This is done to quantify the elemental composition of chemical samples and compounds that may be aqueous or non-aqueous organic or inorganic samples.
- Contamination detection – Advanced laboratory instruments are used to detect chemical contaminants in a particular sample.
- Materials Testing and Chemical Analysis – This is done for all the materials like polymers, plastics, metals, alloys, ceramics etc.
Uses of Chemical Analysis
The qualitative and quantitative chemical analysis finds its use in different industries for ensuring raw material specification, final product quality check, and new product property analysis. This technique also comes in handy for the industry to keep a pollution check by analyzing pollutants in air, liquid, or soil samples.
Advantages of Chemical Analysis
- High accuracy
- Analysis is more representative due to analyses multi-point analysis
Limitation of Chemical Analysis
- Destructive method of analysis causing sample loss
- Not suitable for rapid analysis
Industrial Application of Chemical Analysis
- Metal industry
- Pharmaceutical and medical industry
- Polymer and plastic industry
- Ceramic and paper industry
