
Assayers
Assayers are chemists who conduct laboratory tests on ores and minerals, such as gold, silver, and other metals to determine their properties and value. These specialists use spectrographic analysis and other sophisticated techniques in their work. Assayers remove impurities from the metals and then weigh the residue to determine the proportion of pure components. Those who specialize in the testing and analysis of precious metals are known as gold-and-silver assayers.
Biochemistry
Biochemistry technologists perform chemical analyses of body fluids, such as urine, blood, spinal fluid, and gastric juices, to assist physicians and other health care professionals in the diagnosis and treatment of diseases. First, they prepare the solutions used in the chemical analysis of each specimen. Then they record the quantity of such substances as sugar, drugs, toxins, and blood gases.
Biochemistry technologists test and maintain the laboratory equipment they use—including both manual and computer-controlled analyzers—to ensure that their results are complete and accurate
Biochemists study the chemical processes of living things.
Biochemistry is considered an interdisciplinary science because it combines biology and chemistry to increase our understanding of the structure and biological function of the chemical compounds found in animals and plants. To determine the action of foods, drugs, hormones, and other substances on tissues and life processes, biochemists use such techniques as chromatography and electrophoresis.
Biochemists
Biochemists also examine the precise role of DNA in living things and use their findings to design new types of organisms. This emerging field is known as genetic engineering. Biochemical research benefits people in many different ways. For example, some biochemists study the behavior of normal and abnormal cells to gain a greater understanding of how cancer develops. Others focus their research in the field of agriculture, using biochemical principles to improve the quality and quantity of food crops, as well as their resistance to disease.
Chemical
Chemical engineers develop chemical processes used in the manufacture of a wide variety of goods. Chemical engineers use chemical, physics, and engineering principles to re-create on a large scale what research chemists develop in their laboratories using small amounts of materials. Chemical engineers design and construct the equipment and machinery used in the manufacturing process, and they often supervise the construction of manufacturing plants. In developing their plans, chemical engineers sometimes build “pilot plants”— small-scale testing facilities where they test production capabilities and experiment with new processes.
Chemical engineers estimate the operating costs for a new plant, as well as the number of workers and amount of raw materials necessary to keep the plant running smoothly and efficiently. In addition, they analyze the impact of the new plant on the surrounding environment to ensure that it will not be harmful to air and water quality or wildlife. Chemical engineers work in many different fields, including the electronics, plastics, petroleum, food, and agricultural industries.
Chemical technicians
Chemical technicians assist chemists and chemical engineers in the development, testing, and manufacture of chemical products. Chemical laboratory technicians assist research chemists by analyzing the content, strenght, stability, and purity of materials used in the manufacturing process. The data obtained from these tests are most often used during the research and develoment stages of a product to determine the usefulness of a specific material. Chemical engineering technicians work closely with chemical engineers. They help solve the practical problems of manufacturing products or materials on a large scale after they have been devel oped in the laboratory. They also build, install, test, and maintain the equipment and machinery used in the manufacturing process. Chemical engineering technicians use their test findings to establish efficient operating procedures and recommend changes and modifications that will improve the manufacturing process.

Chemists
Chemists are scientists who study the properties or characteristics of substances, and how these substances act under different conditions. About half of today’s chemists are involved in research and development Some focus on research that solves practical prob-lems, such as improving products and creating new ones. Others conduct basic research to learn more about chemical substances, chemical processes, and the structure and composition of compounds and mixtures. Many chemists work in manufacturing facilities as superintendents or quality-control managers. Chemists also teach at colleges and universities, and assist government agencies involved with environmental protection and public health.
Because chemistry offers a variety of career opportunities, most chemists specialize in a specific area.
Organic chemists study chemical substances that contain carbon-to-carbon bonds, including animal and vegetable matter. Inorganic chemists focus on substances that do not contain carbon-to-carbon bonds, such as metals and minerals. Physical chemists concentrate on the basic theories of chemistry. They interpret chemical processes in the physical properties of matter, such as mass, motion, heat electricity, and radiation. Polymer chemists work with plastics and other chainlike molecules formed by linking many smaller molecules. Synthetic chemists use chemical processes and compounds to duplicate substances that occur in nature, or to produce compounds that do not occur naturally.
Colorists
Colorists develop color formulas for plastics and textile materials, such as fabrics for clothing, draperies, and upholstery. Colorists use their understanding of chemical principles to select dyes and color pigments that will result in the color the customer wants. They also prepare color formulas and mixing procedures for the workers who blend the colors and print the materials. When the materials are printed, colorists examine the finished product to ensure that the color and design placement meet plant quality standards and customer specifications.
Food chemists
Food chemists develop and improve foods, beverages, additives, preservatives, and related products. These specialists also conduct tests and experiments on food products to make sure that they comply with food laws and meet the required standards of quality, safety, and purity. In addition, food chemists study the effects of processing on the properties and composition of food products. They test samples to determine the effects of cooking, canning, freezing, brewing, and distilling on the appearance, taste, texture, aroma, shelf life, and nutrition content of the foods.

Instrumentation chemists
Instrumentation chemists and wastewater-treatment-plant chemists ensure that standards of water-pollution.control are met. At municipal wastewater treatment plants, instrumentation chemists analyze the wastewater discharges of industrial users to make sure that they meet pollution-control requirements. And when an industry is found to be in violation of the law, instrumentation chemists determine how much that industry must pay in fines. These specialists also develop new processes and procedures for analyzing wastewater. Wastewater-treatment-plant chemists examine the by-products of the wastewater-treatment process to ensure that their plants operate efficiently and meet water-pollution requirements.

Perfumers
Perfumers are chemists who develop formulas for perfumes and other aromatic products. After developing their formulas in laboratories, they oversee the manufacturing process to ensure that these products meet quality and production standards. These chemists evaluate large batches of perfume manufactured in the compounding and distilling departments of the perfume factory. In an air-filtered room, they assess each batch by smelling samples dipped in blotter strips. They check specific characteristics, such as odor, body, harmony, strength, and permanence. Perfumers also make sure that batches of the same product manufactured at different times have exactly the same fragrance, color, and level of quality.

Water-purification chemists
Water-purification chemists test filtered water in purification plants and at different points throughout the water distribution system to ensure that quality and purity standards are met. They analyze water samples to confirm that any solids in the system remain below the legal limits.
These specialists also conduct research to determine the type and amounts of chemicals necessary to soften water or make it suitable for drinking. For example, they determine how much liquid chlorine should be used to destroy harmful organisms in water. In addition, when a body of water has been contaminated, water-purification chemists pinpoint the source of contamination by testing samples at various points in the system, such as water mains, pumps, and outlets.