Chemical Glossary

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A        

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• Absolute Pressure  -  A pressure at absolute zero can only exist in a total vacuum and any pressure above this is called absolute pressure.
• Absolute Temperature  -  Measured from the starting point of 0, where zero is the coldest theoretically attainable temperature in nature.
• Absolute Zero  -  Absolute zero is the temperature at which all motion within molecules completely stops.
• Accelerator  -  A compound, usually organic, that greatly reduces the time for a reaction to take place.
• Acid Gas (Sour Gas)  -  Any significant amount of hydrogen sulfide (H2S) and carbon dioxide (CO2) contains a natural gas that can cause corrosion.
• Acid Inhibitor  -  Chemicals that greatly reduce the attack of acids on metal surfaces.
• Actinide Element  -  In the periodic table it is a transition metal.
• Additive  -  Any substance incorporated into a base material.
• Alkali Metal Element  -  They are highly reactive and usually found with other elements in nature, rarely by themselves.
• Alkaline Earth Metal Element  -  These elements are silver colored, soft metals that will only melt at very high temperatures.
• Ammonia  -  A chemical compound made up of nitrogen and hydrogen with the formula \(NH_3\).  It is a colorless gas with a pungent, sharp odor that is easily recognizable.  Ammonia plays an important role in various natural and industrial processes.
• Anion  -  Ions with a negative charge.
• Antiferromagnetic Element -  A family of elements in the periodic table.  A type of magnetism that exist at lower temperatures and disappears at and above a certain temperature.
• Amino Acid  -  A compound of amino and carboxyl groups.
• API Gravity  -  The oil industry uses the API Gravity or Gravity scale.  If a fluids API gravity is greater than 10, it is lighter and floats on water; if less than 10, it is heavier and sinks.
• Atmosphere  -  The gasses around an object in space (planets and stars).
• Atomic Number  -  The number of protons in an element.
• Atomic Number Density  -  The number of atoms of a given type per unit volume of the material.
• Avogadro's Gas Law  -  When temperature and pressure are held constant, the volume of a gas is proportional to the number of moles of gas present.

B         

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• Base  -  A substance which gives of hydroxide ions in solution.
• Biochemical Oxygen Demand  -  The measure of the amount of dissolved oxygen required to decompose matter through a biological oxidation process.
• Blanket Gas  -  A gas phase in a vessel above a liquid phase.  The purpose may be for protecting the liquid from air contamination, for reducing the hazard of detonation, or for pressuring the liquid.  The source of the gas is external to the vessel.
• Boiling Point  -  The temperature at which the atmospheric pressure and the vapor pressure of the liquid become equal.
• Bottoms  -  The liquid or residual matter which is withdrawn from the bottom of a fractionator or other vessel during processing or while in storage.  Also the heaviest product remaining in the liquid phase after distillation.
• Boyle's Law  -  The volume occupied by a given mass of gas varies inversely with the absolute pressure if the temperature remains constant.
• Bubble Point  -  The temperature at a given pressure at the instant the liquid is in equilibrium with the vapor phase in the containing vessel.
• Buffer  -  A compound or mixture, when contained in a solution, causes the solution to resist change in pH.

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• Carbonates  -  The result of a thermal breakdown of bicarbonate in water.
• Carbon Sulfide  -  A chemical coumpound of the aldehyde groups containing a carbonyl group of sulfur (COS).  It is a contaminant gas liquids, usually removed to meet sulfur specifications.
• Casinghead Gas  - The natural gas that is produced from oil wells along with crude oil.
• Catalyst  -  A substance that speeds up a chemical process without actually changing the products of reaction.
• Cathode  -  The electrons flow toward the cathode reducing the corrosion or oxidation of the material.
• Charcoal Test  -  A test standerdized by the American Petroleum Association and the Gas Producers Association to determine the natural gasoline content of a given natural gas.  The gasoline is absorbed from the gas on activated charcoal and then removed by distillation.
• Charle's Law  -  At a constant pressure the volume of a given mass of gas is directly porportional, increases or decreases, to the absolute temperature.
• Chemical Energy  -  When two substances are combined or mixed together (atoms and molecules interacting) to produce a chemical reaction.
• Chemical Formula  -  Expression that states the number and type of atoms in a molecule.
• Chemical Oxygen Demand  -  Not directly related to Biochemical Oxygen Demand. Though it may be sometimes correlated to a specific water with a consistent quality.
• Chemical Property  -  Characteristic that may be observed when matter undergoes a chemical change.
• Chemical Symbol  -  One or two letters that represnets a chemical element.
• Clarifier  -  It is usually the first step in the treatment process since most applications require water that is clear and colorless.
• Closed system  -  A thermodynamics system is a specific quanity of matter with a defined boundary and everything outside the boundary is the surroundings.
• Combined Gas Law  -  The relationship between pressure volume and temperature for a system with a constant amount of gas.
• Combustion  -  A reaction called rapid oxidation or burning produced with the right combination of a fuel, oxygen, and heat.
• Condensation  -  A physical change of a substance from a gas phase to a liquid phase.
• Concentration  -  Concentration is the amount of a substance in solution.
• Corrosion  -  The thinning of a pipe wall that is typically caused by a chemical reaction from a corroding fluid or agent and is limited almost exclusively to metal products.
• Corrosion Inhibitor  -  A material that protects against the wearing away of surfaces.
• Crude  -  A mixture of naturally occuring liquid hydrocarbons before refining.
• Crude Oil Dehydration Facility  -  Prepares the oil for sale by removing water, gas and solids before it is pumped into a pipeline for sale.

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• Dalton’s Law  -  The total pressure of a gas mixture is equal to the sum of the partial pressures of the individual gas components of the mixture.
• Degreaser  -  A specialty product that removes grease and oily soils.
• Dehumidificarion  -  The reduction of water vapor in air by cooling the air below the dew point; removal of water vapor from air by chemical means, refrigeration, etc.
• Density  -  The ratio of the amount of matter in an object compared to its volume.
• Diamagnetic Element -  A family of elements in the periodic table.  A type of magnetism with a very weak magnetic field that will repelled when in the presence of another magnetic field.
• Diatomic Nonmetal Element -  Consist of two atoms bonded togeather.
• Diffusion  -  The spread of gases, liquids, or solids from areas of high concentration to areas of low concentration.
• Distillation  -  The physical process where the separation of various components of a mixture of liquids based on their different boiling points.
• Dry Gas  -  A natural gas with with very little liquid hydrocarbons or water vapor.

E

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• Electrolyte  -  A chemical substance or mixture, liquid or solid, normally liquid, which conducts electric current.
• Electron  -  A particle of an atom that orbits the atom's nucleus and has a negative charge.
• Element  -  Substance that consisting of only one type of atom.
• Emulsion  -  A suspension of small liquid droplets within a second liquid that will not mix.
• Energy  -  Is never created or destroyed.
• Enthalpy  -  Measures the sum of internal energy changes in heat under constant pressure of the system.
• Entropy  -  Measures the unavailable energy in a heat system.
• Ethane  -  A colorless paraffinic gas that boils at a temperature of 127.48 degrees F.

F         

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• Faraday's Law of Induction  -
• Ferromagnetic Element -  A family of elements in the periodic table.  A type of magnetism that forms a strong magnetic field and remains magnetized after the presence of another magnetic field has been removed.
• Ferrous Metal Element -  Since they contain small amounts of metals or added elements they are magnetic and corrode, something non-ferrous metals do not.
• Flare  -  Used in the oil & gas production, a device for the disposal of unwanted gases by burning them off.
• Flash Point  -  The temperature at which combustion is initiated.
• Flue Gas  -  Gas that is emitted to the atmosphere through a pipe as exhaust.
• Fluid  -  A substance that deforms and changes position when put under stress.  Fluids can be both liquids and gases.
• Force  -  The push or pull of an object resulting in a change from rest or motion.
• Free Electron  -  Electron wrich is not attached to a nucleus.
• Freezing  -  A physical change of a substance from a liquid phase to a solid phase
• Freezing Point  -  The temperature where a liquid turns to a solid.
• Frequency  -  Number of events in a given time.
• Fusion  -  The melting togeather of the filler material and base metal or only the base metal.

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• Gas  -  It is able to be compressed to fit a confined space and expanded when released.
• Gasoline  -  Gasoline is a blend of refined crude oil products.  It is a complex mixture contain hundreds of different compounds by the time there is a finished product.
• Gas laws  -
• Gas Processing Plant  -  A plant which processes natural gas for recovery of natural gas liquids and sometimes other substances such as sulfur.
• Gas-well Gas  -  The gas produced or seperated at surface conditions from the fuel well stream produced from a gas resivoir.
• Gas-well Liquid  -  the liquid seperated at surface conditions from the full well stream produced from a gas resivoir.
• Gasoline  -  Petroleum derived liquid used as transportation fuel.
• Gathering System  -  The network of popelines which carry gas from the wells to the processing plant or other separation equipment.
• Gay-Lussac's Law  -  When temperature increases, pressure increases, when pressure decreases, temperature decreases.
• Graham's Law  -  The rate at which gases disperse is inversely proportional to the square root of their mass.

H         

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• Heat  -  A form of energy that causes physical change in what is being heated.
• Heat Capacity  -  The ratio of heat transferred to raise the temperature of an object.
• Heat Transfer  -  The exertion of power that is created by heat, or the increase in temperature.
• Heavy Crude  -  Crude oil with a high proportion of heavy hydrocarbon fractions and metallic content.
• Heavy Metal  -  A heavy metal that is toxic at low concentrations.
• Henry's Law  -  At a constant temperature, the volume of a gas which will dissolve into a solution is directly porportional to the partial pressure of that gas above the solution in equilibrium with the liquid.
• Hydrocarbon  -  Chemical compound containing hydrogen and carbon.
• Hydrogen  -  The lightest of all gases, occuring mainly in combination with oxygen in water.  Hydrogen is the simplest and most abundant chemical element in the universe, represented by the symbol \(H\) and atomic number 1.  It is a colorless, odorless, and tasteless gas under standard conditions and is composed of diatomic molecules (\(H_2\)) in its natural form.

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• Ideal Gas Law  -  Can be used to predict pressure, temperature & volume changes in ideal gasses.
• Internal Energy  -  The total of all energies associated with the motion of the molecules in the system.
• Ion  -  A term that defines an electrical charge on an atom or group of atoms.
• Isolated System  -  A thermodynamics system is a specific quanity of matter with a defined boundary and everything outside the boundary is the surroundings.

J

K         

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• Kinetic Energy  -  The energy in moving objects or mass.

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• Lanthanide  -  A silvery white, malleable, ductile, and soft enough to be cut with a knife.
• Law of Conservation of Energy  -  States that energy cannot be created or destroyed, but may be changed from one form to another.
• Law of Conservation of Mass  -  States that matter can neither be created or destroyed.
• Light Crude  -  Crude oil with a light proportion of light hydrocarbons fractions and low metallic compounds.
• Lime Softening  -  Lime softening is a common way to to soften water.  It involves the removal of impurities by chemical reaction with combinations of lime, soda ash (sodium carbonate) and caustic.
• Liquid -  Has a specific volume and can hold any shape it is contained within.

M         

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• Magnetic Element  -  The elements that are capable or becoming magnetic.
• Mass  -  The amount of matter an object has.
• Matter  -  If it has a mass and takes up space, it is matter.
• Melting  -  A transitional phase from solid to liquid.
• Melting Point  -  A change in temperature at which a solid changes to liquid.
• Metalloid Element  -  Elements that fall between metals and non-metals having some of the properties of metals but not all.
• Metal Element  -  The physical properties of metals have characteristic such as shiny, hard, high density, malleable, high melting point and can conduct electricity and heat well.
• Methane  -  Simplest alkane, hydrocarbon that is the largest component of natural gas.  Chemical formula \(CH_4\).
• Methanol  -  A light, volatile alcohol intended for gasoline blending.
• Mineral Salts  -  The form in which minerals from dissolved rock exist in water.
• Mixture  -  A combination of two or more substances that are not chemically combined.
• Molar Mass  -  The mass of a given compound equal to its molecular mass in gram.
• Molarity  -  Describes the concentration of a solution (substance being dissolved). 
• Molar Mass  -  The mass of a given compound equal to its molecular mass in gram.
• Mole  -  The measurement of a mass of a substance in grams in the international system of units (SI).
• Molecule  -  A group of two or more atoms that are chemically bonded together.  These atoms can be of the same element, such as \(O_2\)​ (oxygen gas), or different elements, like \(H_2 O\) (water).  Molecules are the smallest units of a chemical compound that retain the compound's chemical properties.
• N         

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• Natural Gas  -  A naturally occuring hydrocarbon gas consisting primarly of methane.
• Natural Gasoline  -  A mixture of hydrocarbons, mostly pentanes and heavier, extracted from natural gas, which meets vapor pressure, end point, and other specifications for natural gasoline.
• Neutron  -  A particle in the nucleus of an atom that has no electric charge.
• Noble Gas -  They are all oderless, colorless, monatomic gasses with very low chemical reactivity.
• Monatomic Element  - Consist of single atoms.
• Non-ferrous Metal Element  -  Do not contain iron.  Due to the lack of iron they are not magnetic and are usually more resistant to corrosion than ferrous metals.  This makes these metals more durable than iron, easier to be processed and able to be formed.
• Nonmetal Element  -  Usually have a relative low melting point, boiling point, and density.
• Nucleus  -  The center core of an atom containing the protons and neutrons.
• Neutron  -  A non-charged nuclear particle with the same mass as the proton.

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• Odorant  -  A highly odiferous fluid of gas, usually a light mercaptan, added to the gas or LP gas to impart to it a distinctive odor for safety precautions and to facilitate detection of leaks.
• Oil Sand  -  Mixture of clay, sand, water, and bitumen.
• Oil Well Gas  -  fgas that is produced from an oil well.
• Open System  -  A thermodynamics system is a specific quanity of matter with a defined boundary and everything outside the boundary is the surroundings.
• Organic Contaminant  -  Carbon-based chemicals, such as solvents and pesticides, which enter water through cropland runoff or discharge from factories.
• Oxidation  -  The loss of electrons in a chemical reaction in which an element combines with oxygen.  Oxidation and reduction always occur at the same time in equal amounts.
• Oxidation Atmosphere  -  An atmosphere which tends to promote the oxidation of immersed materials.
• Oxygen Deficient Atmosphere  -  An atmosphere containing less than 19.5 percent oxygen by volume.
• Oxygen Enriched Atmosphere  -  An atmosphere containing more than 23.5 percent oxygen by volume.
• Oxident  -  A reactant that oxidizes or removes electrons from another reactant in a redox reaction.
• Oxidizing Gas  -  A gas that can support and accelerate combustion of other materials.
• Oxigen Index  -

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• Paramagnetic Element -  A family of elements in the periodic table.  A type of magnetism with a very weak magnetic field that will only happen when in the presence of another magnetic field.
• Periodic Table  -  A table of the chemical elements arranged by atomic number.
• pH  -  A scale that indicates the degree of acidity or alkalinity of a solution.
• Pipeline Gas  -  AGas which meets a transmission company's minimum specifications.
• Plasma  -  It is everywhere in the universe and the most common of all matter.
• Polyatomic Nonmetal Element -  They are all solid, mostly semi-lustrous semiconductors with electronegativity values that are intermediate to moderately high.
• Polymer  -  Materials made of long, repeating chains of molecules.  Some bend and stretch like rubber, others are hard and rough like glass.
• Post-transition Metal Element  -  They have poor mechanical strength with melting points lower than transition metals.
• Pressure  -  It is the force exerted perpendicular to the surface of an object and is expressed as force per unit area.
• Propane  -  A normally gaseous paraffinic coumpound (\(C_3\;H_8\)).
• Protein  -  A compound consisting of 50 or more amino acids.
• Proton  -  A particle within the nucleus of an atom that holds a positive charge.

Q

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• Radioactive Element  -  There are stable and unstable atoms.  Stable atoms remain the same forever.  Radioactivity comes from unstable atoms having too much energy, breaking down and decaying.  During this process new atoms are created.
• Raoult's Law  -  The vapor pressure of a solution is changed by the addition of a solute.
• Rate of Reaction  -  The amount of product made in a certain time.
• Ratio  -  The comparison between two quantities or dividing one number by another.
• Raw Gas  -  Unprocessed gas or the inlet gas to a plant.
• Raw Mixed Liquids  -  A mixture of natural gas liquids prior to fractionation.
• Reaction  -  A chemical change that forms new substances.
• Redox  -  A reversible chemical reaction in which one reaction is an oxidation and the reverse is a reduction.
• Feflux  -  In the distilation process, that part of the condensed overhead steam that is returned to the fractionating column as a source of cooling.
• Relative Density  -  The density or ratio of any substance relative to another substance.

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• Salinity  -  Used to describe the "saltiness" of a water.
• Single Bond  -  When an electron pair is shared by two atoms.
• Solid  -  Has particles that are compressed together in an orderly pattern.
• Solute  -  Substance that is dissolved in a chemical solution.
• Solubility  -  Maximum amount of solute that may be dissolved in a specific solute.
• Solution  -  Homogenous mixture of two or more substances.
• Solubility  -  The maximum amount of solid that can be dissolved in a liquid at a specific temperature.
• Solvent  -  A liquid with the capability to dissolving another substance to form a uniformly dispersed mixture.
• Sour Crude  -  Crude oil with a sulfur content higher than 0.5% by weight.
• Sour Gas  -  See acid gas
• Specific Gravity  -  The density or ratio of any substance to another substance.
• Specific Heat  -  The amount of heat required to raise the temperature of a material 1 degree.
• Specific Heat Capacity  -  The amount of energy required to increase the temperature of the substance by 1°C.
• Stripping Medium  -  The medium is steam, gas, or other laterial that will increase the driving force fro stripping.
• Steam  -  The invisible vapor (gas) when water is heated to its boiling point and passes from a liquid to a gaseous state.
• Strong Base  -  A base that completely dissociates into its ions in a watery solution.
• Surface Tension  -  The energy or force at the surface of a liquid that holds it together.
• Suspension  -  Widely dissimilar elements mixture of solid particles in a fluid.
• Sweet Gas  -  Gas that has no more than the maximum sulfur content.

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• Tail Gas  -  The lightest hydrocarbon gas released from a refining process.
• Temperature  -  Normally described as the amount of heat or cold, but it is neither heat or cold.
• Transition Metal Element  -  These elements are both ductile and malleable, and conduct electricity and heat.
• Triple Point  -  A place where temperature and pressure of the three phases, liquid, solid , and vapor, coexist at equilibrium.

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• Universal Gas Constant  -  The gas constant is the Boltmann constant in units of energy per temperature per mole.
• Universal Solvent  -  A chemical that disolves most substances.
• Unsaturated Compound  -  Hydrocarbon compounds having one or more unsaturated carbonvalence bonds.

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• Vacuum  -  A contained space having little or no matter or a volume having a pressure lower than the outside atmospheric pressure.
• Vapor  -  The gas state of a liquid or solid.
• Vapor Density  -  Whether a substance is heavier or lighter than air, which has a vapor density of 1.  A vapor with a density lighter than 1 is lighter than air and will rise in air.
• Vapor Pressure  -  The pressure at a certain temperature when the liquid and vapor are in equilibrium.
• Vapor Pressure Gasoline  -  A descriptive phase for natural gasoline meeting a specified vapor pressure.
• Vapor Recovery  -  Equipment or process for the recovery of the desired components from stock tank vapors or vapors from some other source.
• Vaporization -  A physical change of a substance from a liquid phase to a gas phase.
• Viscosity  -  The measure of the internal friction/resistance to the flow of a liquid.
• Volume  -  The space occupied by a mass.

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• Water  -  Can exist in three of the four phases of matter: gas, liquid, or solid.
• Wavelength  -  The distance between the crests of a wave.
• Weak Base  -  A base that only partially separates in water.
• Weight  -  When you think of weight, it is probably associated with mass.  But weight is not mass.  Weight is a force on an object accelerated by gravity.
• Wet Gas  -  A gas containing a relatively high portion of hydrocarbons that are recoverable as liquids.
• Wetting Agent  -  A compound that increases the ability and speed with which a liquid displaces air from a solid surface.
• Work  -  The overcoming of resistance through space.
• Working Solution  -  A chemical solution prepared for use in a lab.

X

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• Yield  -  The quantity of a product obtained from a chemical reaction.

Z