### person | scientist:

Chemist
* Every chemist knows that it has two parts, a cation and an anion.
* Many chemists are interested in molecules and compounds
  - do research and create new things
  - enter management after beginning their careers in a technical position
  - favour supramolecular chemistry
  - prefer to use the term molar mass for the mass of a mole of substance
  - seek employment in the health-care professions after graduate work
  - use Argon as a carrier gas to make the plasma
* Many chemists work in research and development laboratories in industry
* Most chemists analyze samples
  - believe that the electronic structure of benzene is delocalized
  - determine equilibrium constants in a solution with a high ionic strength
  - evaluate properties
  - identify materials
  - investigate products
  - specialize in methods
  - study atmospheric components
* Most chemists understand air
  - structures
* Most chemists use alcohol
  - elements
  - microscopes
  - their research skills to formulate, produce, and analyze new compounds
* Most chemists work for companies
  - industries
  - private industries
* Most chemists work in facilities
  - labs
* Most chemists work on computers
  - procedures
  - regular hours in well-equipped labs, offices, or classrooms
  - with departments
* Some chemists conduct basic research to expand knowledge of the field.
* Some chemists create color
  - discover oxygen
  - do field work
  - have a knack for using annelations to alter the nature of molecules
  - look at metabolism
  - prefer self-employment through small business or consulting firms
  - realize products
  - restrict the term to compounds with the charges on non-adjacent atoms
  - start their own businesses or work as consultants
  - study air pollution and reactions in the upper atmosphere
* Some chemists use acid
  - graphite
  - watch what happens when they mix two or more chemicals together
* Some chemists work around dangerous chemicals
  - for research organizations and educational institutions
* Some chemists work in marketing, sales, or computer programming
  - production and inspection
* Some chemists work with biologists
  - material scientists
* add chemicals.
* also can precipitate substances out of the air
  - count atoms when naming a sigmatropic shift where a hydrogen atom moves
  - design and develop instruments to study matter
  - pursue academic careers at high schools, colleges and universities
  - record and report on test results
  - search for new chemicals in nature or they make up new ones
  - seek to understand chemical changes
* also sell cosmetics and insect and sun protections
  - cosmetics, insect and sun protections
  - use computers to form molecules
* also work in chemical manufacturing plants
  - factories
  - production and quality control in chemical manufacturing plants
  - on environmental problems, collecting samples of plants and animals for analysis
* always use the molecular formula, if there is one, in preference to an empirical formula.
* analyze and experimentally test chemical substances
  - reactions to determine the properties of matter
* analyze, synthesize, quantitate and design materials.
* analyzes blood for drugs and poisons.
* apply their knowledge of chemistry in various ways
  - to problems of the environment, energy, medicine and agriculture
* are also at the forefront of developing fields such as nanotechnology
  - concerned about the handedness of molecules
  - experts on the behavior of molecules
  - highly paid professionals
  - in high demand in industrial, government and academic laboratories
* are interested in the composition, properties and transformations of matter
  - properties of substances
  - located in chemistry labs
* are people who like to solve problems
  - study compounds and find new ways to do chemical reactions
  - physical scientists that specialize in the study of matter
  - science career professional doing extraordinary work
  - scientists, technicians, managers, producers, teachers, and always, problem solvers
  - surer than ever that they are now 'seeing' atoms
  - trained in analyses
* call the calcium-fatty acid product a grease or metallic soap or salt
  - first category ethers and the second category alcohols
* can also use several different chemical reactions to separate carbon dioxide
  - apply their knowledge of chemistry to various purposes
  - classify matter as solid, liquid, or gas
  - have involvement
* can use it to see how organic materials react with each other
  - spectroscopy to identify chemical compounds as well as elements
* carefully measure substance proportions, reaction rates, and other chemical properties.
* change the molecules in the petroleum and create many new products.
* characterize fluoride as a poison.
* classify matter in order to better understand and describe it.
* come in all shapes and sizes and all socio-economic backgrounds.
* commonly abbreviate acetic acid using the symbolic formula, HOAc.
* consider hard ionization to be shooting electrons into the sample molecules.
* construct knowledge by systematically examining quantitative data for patterns.
* contribute to such diverse fields as medicine, agriculture, oceanography, and archaeology.
* create new compounds.
* design commercial polymers to combine the best properties of their various components.
* desire to know nature and work within natural laws.
* detect certain air and water pollutants by using fluorescence.
* develop coloring agents, preservatives and flavours, which are safe for food use
  - colourants, preservatives and flavours, which are safe for food use
  - products, test quality control, monitor the environment, and control pollution
  - theories
* disagree whether some reactions are pericyclic reactions.
* discover concepts
* dissolve celluloid in ether or acetone to make collodion.
* divide energy into two classes.
* do experiments to learn how matter is composed
  - fundamental research on the properties and reactions of substances
  - it organically and inorganically
* don t argue about where to put newly discovered elements in it.
* explore potential of dendritic macromolecules as functional materials.
* find jobs in every sector of manufacturing, from home products to pharmaceuticals.
* generally combine the complex wave functions to create new wave functions that are real.
* get carbon dioxide from cooling air.
* have a whole shorthand notation for representing the structure of chemical compounds
  - active collaborations with biologists, physicists, geologists, and engineers
* have many different ways of putting together an understanding of something
  - strategies to find the best sequence of reactions to make the desired product
  - professional obligations to the public, to colleagues, and to science
  - responsibility to avoid pollution and to protect the environment
  - responsiblity to avoid pollution and to pretect the environment
  - similar problems observing individual molecules in reactions
  - tailored microscopic beads to sop up and permanently bind toxic waterborne pesticides
  - what they call chemical abstracts
  - the molecules, both natural and man-made, that exist in the environment
* includes arms
  - body substances
  - cell membranes
  - cells
  - corpi
  - cytoplasm
  - heads
  - human bodies
  - legs
  - material bodies
  - necks
  - nuclei
  - personality
  - plasma membranes
  - sections
  - vacuoles
* invent new substances and develop theories to explain chemical reactions or processes.
* investigate new products
  - properties of matter and the laws that come into play when elements combine
* isolate the active chemicals and determine their structures.
* keep records and prepare reports showing results of tests.
* learn to knot their molecules.
* like to experiment
  - work with pure substances
* make contributions
  - statements
* measure acidity using pH. An acid has a low value of pH and a base has a higher value.
* need computer skills
* often identify elements from their physical properties
  - label orbital energies with the lower case Greek letter epsilon
  - melt the reactants together and then later anneal the solidified melt
  - mix compounds together creating new substances with different physical properties
* often specialize in a particular branch of the field
  - subfield
  - one of the subfields of chemistry
  - study problems by constructing models
  - use hydrogen peroxide in chemical reactions
* perform experiments to measure the equilibrium constant of various reactions.
* prefer to think in terms of moles of material, however.
* prepare new compounds and study their composition and structure.
* recognise that hydrogen is an unusual element.
* say the materials damaged by ozone include rubber, nylon, plastics, dyes, and paints.
* search for and put to practical use new knowledge about chemicals
  - use new knowledge about substances
* see importance.
* seem to form a significant group of winemakers.
* serve society in a variety of ways to improve the quality of life.
* sometimes find it necessary to specify the atomic mass of an isotope.
* sort the MOs by energy levels.
* spin materials to improve magnetic resonance data.
* start to design a chemical synthesis by selecting compounds to combine.
* study all things that have mass and occupy space, making chemistry the central science
  - and work with chemicals
  - atomic orbital interactions
  - atoms as well as the structures and reactions of molecules
  - characteristics
  - many different fields
  - molecules to see how they change, how they form, and how they move
  - symmetry to explain how crystals are made up and how chemicals react
  - the atomic structure of physical matter and analyze how it changes
* study the composition and properties of matter and energy
  - of substances, how the substances act, and how they change
  - makeup of substances and the ways they combine and react with each other
  - structure and behavior of chemicals
  - structures, physical properties, and chemical properties of material substances
* talk about entropy and activation energy when they talk about chemical reactions.
* tend to become deeply involved in their work
  - enjoy an unemployment rate that is significantly less than the national average
  - mold a nanostructure
  - organize atoms together to grow a nanostructure
  - synthesize esters in a two-step process
* test liquid mixture
* therefore distinguish hydrogen chloride from hydrochloric acid.
* think they are physical chemists.
* try to choose names that provide information about the chemical.
* typically work regular hours.
* undertake responsibility.
* use a formal language to represent the chemical structure of molecules
  - process called reverse osmosis to purify water and perform other functions
  - solvent such as ether or alcohol in the extractor
  - technique called chromatography to accomplish much of the needed separation
  - atoms and molecules to explain properties and behaviors of matter
  - blends
  - catalysts to speed up slow reactions
  - chemical equations to express what occurs in chemical reactions
  - clay and sticks to form models of molecules
  - entropy as a tool for understanding spontaneous change
  - equations to describe the changes substances undergo
  - hybridization theory mainly in organic chemistry
  - hydriodic acid in experiments as a powerful reducing agent
* use it as a solvent for chemical reactions and in cromatography
  - to remove a material from a solid
  - methyl orange as an indicator in the titration of weak bases with strong acids
  - molarity to express quantitatively the concentration of a solution
  - molecular models for a variety of reasons
  - one or two lettters to represent elements
  - pH as a measure of how acidic or basic a compound is
  - reaction diagrams to predict reactions in a test tube
  - sensitive magnetic equipment to measure simple and complex molecules
  - several definitions to describe the behavior of acids
  - special kinds of graphs to represent chemicals
  - specific knowledge
  - spectroscopy, the utilization of electromagnetic radiation, to study matter
  - strong acids to break down other molecules
* use such data to work out the molecular structure of substances they wish to analyze
  - functions to predict or explain chemical and physical properties
  - superacids to make plastics and high-octane gasoline
* use symbols to represent elements
  - stand for the elements
* use the graph to calculate fundamental quantities
  - scientific method when they investigate matter
* usually build mathematical models of molecular orbitals by combining atomic orbitals.
* usually refer to proteins as polypeptides
  - the wave function of the H atom as the atomic orbital of the atom
* usually work as part of a team
  - in offices and laboratories
* work as professionals in virtually every industry, business and research organization
  - teams
  - toy companies
* work in all fields of modern civilization, academe, government, and industry
  - every sector - including academia, the private sector, and the government
  - sales for chemistry related companies
  - the pharmaceutical, paper, oil, biotechnology and consumer product industries
  - important problems and tackle the challenges posed by our ever-changing world
* work with departments
  - engineers, who in turn work with modern-life scientists
* working in applied research use their knowledge to improve and create new products.
+ Acetonitrile: Chemical compounds :: Organic compounds
  * It is a clear liquid and is the simplest molecule in a group called nitriles. Acetonitrile is made when plastics are being made so is quite cheap. Chemists use it as a solvent for chemical reactions and in cromatography.
+ Carbon dioxide, Isolation and production: Organic compounds :: Biochemistry :: Greenhouse gases :: Oxides
  * Chemists get carbon dioxide from cooling air. They call this air distillation. But this method is inefficient. Chemists can also use several different chemical reactions to separate carbon dioxide. Carbon dioxide is made in the reactions between most acids and most metal carbonates.
+ Chemical synthesis, Strategies
  * Chemists have many strategies to find the best sequence of reactions to make the desired product. In cascade reactions multiple chemical changes take place within a single reactant. In multi-component reactions up to 11 different reactants form a single reaction product. In a telescopic synthesis, one reactant goes through multiple transformations without isolating intermediates after each step
  - synthesis: Chemistry
  * Chemists start to design a chemical synthesis by selecting compounds to combine. These starting compounds are known as reagents or reactants. Chemists use various reaction types to these to synthesize the product, or an intermediate product. This requires mixing the compounds in a reaction vessel. Many reactions require some form of work-up procedure before the final product is isolated. Vogel's Textbook of Practical Organic Chemistry, 5th Edition'
+ Equilibrium constant
  * For equilibria in solution, activity is the product of concentration and activity coefficient. Most chemists determine equilibrium constants in a solution with a high ionic strength. In high strength solutions, the quotient of activity coefficients changes very little.
  * This is more likely to happen if the reactants have a higher concentration. So, the concentrations of all the necessary pieces are multiplied together to get the probability that they will be in the same place for the reaction. Going the other way, all of the concentrations of those necessary pieces are multiplied together to get the probability that they will be in the same place to react in the opposite direction. The ratio between those two numbers represents how popular each side of the reaction will be when equilibrium is reached. An equilibrium constant of 1 means that both sides are equally popular. Chemists perform experiments to measure the equilibrium constant of various reactions.
+ Gas chromatography–mass spectrometry, Analysis, Types of ionization, Electron ionization: Mass spectrometry :: Laboratory techniques
  * This is like the filament one would find in a standard incandescent light bulb. The electrons hit the molecules, causing the molecule to fragment in a characteristic way that can be repeated. EI has few, if any, fragments having a mass that is near the mass of the original molecule. Chemists consider hard ionization to be shooting electrons into the sample molecules. The use of 70 eV helps to compare the spectra generated from the test sample against known library spectra. The software searches the library spectra using a matching algorithm such as Probability Based Matching or dot-product matching. Many method standardization agencies now control these algorithms and methods to assure their objectivity.
+ Hydrogen halide
  * The hydrogen halides are diatomic molecules with no tendency to ionize in the gas phase. Chemists therefore distinguish hydrogen chloride from hydrochloric acid. The former is a gas at room temperature that reacts with water to give the acid. Once the acid has formed, the diatomic molecule can not easily be regenerated
  - peroxide: Chemical compounds :: Oxygen compounds :: Hydrogen compounds
  * Chemists often use hydrogen peroxide in chemical reactions. Oxidising agents' take electrons from other compounds
+ Inductively coupled plasma mass spectrometry: Mass spectrometry :: Laboratory equipment :: Analytical chemistry
  * Many chemists use Argon as a carrier gas to make the plasma. The machine sends the sample ions through a series of small cones. The cones let the plasma ions slowly enter the vacuum chamber of the mass spectrometer.
+ Molecular orbital, Formation of molecular orbitals
  * Chemists study atomic orbital interactions. The overlap is important if the atomic orbitals are close in energy. Finally, the number of MOs in a molecule must equal the number of atomic orbitals in the atoms being brought together to form the molecule
  - Qualitative approach, HOMO and LUMO
  * Each molecular orbital has its own energy level. Chemists sort the MOs by energy levels. Chemists assume that the electrons will fill the lowest energy level MOs first. For example, if a molecule has electrons to fill 15 orbitals, the 15 MOs with the lowest energy levels will be filled. The difference in the HOMO's energy level and the LUMO's energy level is called the band gap
  - orbital: Physics :: Quantum chemistry :: Theoretical chemistry :: Computational chemistry :: Chemical bonding
  * A MO is a mathematical function which describes the wave-like behaviour of an electron in a molecule. Chemists use such functions to predict or explain chemical and physical properties. For example, the functions can tell the probability of finding an electron in any specific region.
  * Chemists usually build mathematical models of molecular orbitals by combining atomic orbitals. Hybrid orbitals from each atom of the molecule, or other molecular orbitals from groups of atoms can also be used. Computers can work on these functions. Molecular orbitals allow chemists to apply quantum mechanics to study molecules. MOs answer questions about how the atoms in molecules stick together. The various rounded shapes in an orbital diagram indicate where electrons would most likely be found in an atom
  - symmetry, Point groups, Representations
  * Chemists use the irreps to sort the symmetry groups and to talk about their properties
  - symmetry: Symmetry :: Theoretical chemistry
  * In chemistry, 'molecular symmetry' is the symmetry of molecules. It also puts molecules into groups according to their symmetry. Molecular symmetry is a basic idea in chemistry. It can predict or explain many of a molecule's chemical properties, such as its dipole moment. Chemists study symmetry to explain how crystals are made up and how chemicals react. The molecular symmetry of the reactants help predict how the product of the reaction is made up and the energy needed for the reaction
+ Orbital hybridization, Historical development: Chemical bonding :: Quantum chemistry :: Stereochemistry
  * In the case of simple hybridization, this approximation is based on atomic orbitals. In heavier atoms, like carbon, nitrogen, and oxygen, the atomic orbitals involved in bonding are the 2s and 2p orbitals. These orbitals can be occupied in a hydrogen atom, but only when the electron is in an excited state. Hybrid orbitals are assumed to be mixtures of these atomic orbitals, superimposed on each other in various proportions. It provides a quantum mechanical insight to Lewis structures. Chemists use hybridization theory mainly in organic chemistry.
+ Pericyclic reaction: Pericyclic reactions :: Rearrangement reactions
  * Many pericyclic reactions have similar stepwise radical processes connected with them. Chemists disagree whether some reactions are pericyclic reactions. Many pericyclic reactions have similar reactions that are metal-catalyzed. But these metal-catalyzed reactions are also not really pericyclic. The metal catalysts stabilize the reaction intermediates. So the reaction is not concerted, but rather metal-stabilized.
+ Polymer chemistry, History
  * Polymer chemistry started by studying the long fibers in plants. Nitrocellulose treated with camphor makes celluloid. Chemists dissolve celluloid in ether or acetone to make collodion. Doctors have used collodion as a wound dressing since the U.S. Civil War. Cellulose acetate was first prepared in 1865. In 1844 Charles Goodyear received a U.S. patent for vulcanizing rubber with sulfur and heat. Thomas Hancock had received a patent for the same process in the UK the year before.
  * There are now a large number of commercial polymers. Chemists design commercial polymers to combine the best properties of their various components. For example, special polymers used in automobile engines are designed to work at high temperatures.
+ Sigmatropic reaction, Overview of Sigmatropic Shifts, Woodward-Hoffman Sigmatropic Shift Nomenclature
  * Chemists also count atoms when naming a sigmatropic shift where a hydrogen atom moves. The carbon chain does not break in a hydrogen atom migration. So, chemists count across all atoms involved in the reaction rather than only across the closest atoms.
+ Solid-state chemistry, Synthetic methods, Oven techniques, Melt methods
  * Chemists often melt the reactants together and then later anneal the solidified melt. If volatile reactants are involved, the reactants are often put in an ampoule and then all air is removed. The sealed ampoule is then put in an oven and given a specified heat treatment.
+ Soxhlet extractor, Uses
  * Chemists use it to remove a material from a solid. It is useful when removing materials that do not dissolve well in any solvent. Chemists use a solvent such as ether or alcohol in the extractor. The Soxhlet extractor applies the solvent repeatedly to the solid until enough of the material dissolves.
  * Chemists are people who study compounds and find new ways to do chemical reactions. They make chemicals in order to find new ways to do things, like to make a better glue, or to make new medicines, or to make things clean, for example. They also use compounds to find out more about the laws of chemistry.
+ Superacid: Acids
  * Chemists use strong acids to break down other molecules. Supercids can break down molecules that stand up to most other acids.
+ Thermochemistry, Calorimetry: Physical chemistry
  * The temperature of the chamber is measured either using a thermometer or thermocouple. The temperature is plotted against time to give a graph. Chemists use the graph to calculate fundamental quantities.