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A solvent (s) (from the
Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
'' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a
solution Solution may refer to: * Solution (chemistry), a mixture where one substance is dissolved in another * Solution (equation), in mathematics ** Numerical solution, in numerical analysis, approximate solutions within specified error bounds * Soluti ...
. A solvent is usually a liquid but can also be a solid, a gas, or a
supercritical fluid A supercritical fluid (SCF) is any substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist, but below the pressure required to compress it into a solid. It can effuse through porous so ...
. Water is a solvent for
polar molecules In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment, with a negatively charged end and a positively charged end. Polar molecules must contain one or more polar ...
and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell. The quantity of
solute In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. If the attractive forces between the solvent ...
that can dissolve in a specific volume of solvent varies with
temperature Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature is measured with a thermometer. Thermometers are calibrated in various temperature scales that historically have relied o ...
. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. Specific uses for organic solvents are in
dry cleaning Dry cleaning is any cleaning process for clothing and textiles using a solvent other than water. Dry cleaning still involves liquid, but clothes are instead soaked in a water-free liquid solvent. Tetrachloroethylene (perchloroethylene), known in ...
(e.g.
tetrachloroethylene Tetrachloroethylene, also known under the systematic name tetrachloroethene, or perchloroethylene, and many other names (and abbreviations such as "perc" or "PERC", and "PCE"), is a chlorocarbon with the formula Cl2C=CCl2 . It is a colorless li ...
); as
paint thinner A paint thinner is a solvent used to thin oil-based paints. Solvents labeled "paint thinner" are usually mineral spirits having a flash point at about 40 °C (104 °F), the same as some popular brands of charcoal starter. Common solv ...
s (
toluene Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon. It is a colorless, water-insoluble liquid with the smell associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) at ...
,
turpentine Turpentine (which is also called spirit of turpentine, oil of turpentine, terebenthene, terebinthine and (colloquially) turps) is a fluid obtained by the distillation of resin harvested from living trees, mainly pines. Mainly used as a special ...
); as nail polish removers and solvents of glue (
acetone Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscib ...
,
methyl acetate Methyl acetate, also known as MeOAc, acetic acid methyl ester or methyl ethanoate, is a carboxylate ester with the formula CH3COOCH3. It is a flammable liquid with a characteristically pleasant smell reminiscent of some glues and nail polish remo ...
,
ethyl acetate Ethyl acetate ( systematically ethyl ethanoate, commonly abbreviated EtOAc, ETAC or EA) is the organic compound with the formula , simplified to . This colorless liquid has a characteristic sweet smell (similar to pear drops) and is used in glues ...
); in spot removers (
hexane Hexane () is an organic compound, a straight-chain alkane with six carbon atoms and has the molecular formula C6H14. It is a colorless liquid, odorless when pure, and with boiling points approximately . It is widely used as a cheap, relatively ...
, petrol ether); in detergents ( citrus terpenes); and in
perfume Perfume (, ; french: parfum) is a mixture of fragrant essential oils or aroma compounds (fragrances), fixatives and solvents, usually in liquid form, used to give the human body, animals, food, objects, and living-spaces an agreeable scent. Th ...
s (
ethanol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl ...
). Solvents find various applications in chemical,
pharmaceutical A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and re ...
, oil, and gas industries, including in chemical syntheses and purification processes.


Solutions and solvation

When one substance is dissolved into another, a
solution Solution may refer to: * Solution (chemistry), a mixture where one substance is dissolved in another * Solution (equation), in mathematics ** Numerical solution, in numerical analysis, approximate solutions within specified error bounds * Soluti ...
is formed. This is opposed to the situation when the compounds are
insoluble In chemistry, solubility is the ability of a substance, the solute, to form a solution with another substance, the solvent. Insolubility is the opposite property, the inability of the solute to form such a solution. The extent of the solubil ...
like sand in water. In a solution, all of the ingredients are uniformly distributed at a molecular level and no residue remains. A solvent-solute mixture consists of a single
phase Phase or phases may refer to: Science *State of matter, or phase, one of the distinct forms in which matter can exist *Phase (matter), a region of space throughout which all physical properties are essentially uniform * Phase space, a mathematic ...
with all solute molecules occurring as ''solvates'' (solvent-solute complexes), as opposed to separate continuous phases as in suspensions, emulsions and other types of non-solution mixtures. The ability of one compound to be dissolved in another is known as solubility; if this occurs in all proportions, it is called
miscible Miscibility () is the property of two substances to mix in all proportions (that is, to fully dissolve in each other at any concentration), forming a homogeneous mixture (a solution). The term is most often applied to liquids but also applies ...
. In addition to mixing, the substances in a solution interact with each other at the molecular level. When something is dissolved, molecules of the solvent arrange around
molecule A molecule is a group of two or more atoms held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions which satisfy this criterion. In quantum physics, organic chemistry, and bioch ...
s of the solute.
Heat transfer Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, ...
is involved and
entropy Entropy is a scientific concept, as well as a measurable physical property, that is most commonly associated with a state of disorder, randomness, or uncertainty. The term and the concept are used in diverse fields, from classical thermodynam ...
is increased making the solution more
thermodynamically stable In chemistry, chemical stability is the thermodynamic stability of a chemical system. Thermodynamic stability occurs when a system is in its lowest energy state, or in chemical equilibrium with its environment. This may be a dynamic equilibriu ...
than the solute and solvent separately. This arrangement is mediated by the respective chemical properties of the solvent and solute, such as
hydrogen bonding In chemistry, a hydrogen bond (or H-bond) is a primarily electrostatic force of attraction between a hydrogen (H) atom which is covalently bound to a more electronegative "donor" atom or group (Dn), and another electronegative atom bearing a l ...
, dipole moment and
polarizability Polarizability usually refers to the tendency of matter, when subjected to an electric field, to acquire an electric dipole moment in proportion to that applied field. It is a property of all matter, considering that matter is made up of elementar ...
. Solvation does not cause a chemical reaction or chemical configuration changes in the solute. However, solvation resembles a
coordination complex A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many ...
formation reaction, often with considerable energetics (heat of solvation and entropy of solvation) and is thus far from a neutral process. When one substance dissolves into another, a solution is formed. A solution is a homogeneous mixture consisting of a solute dissolved into a solvent. The solute is the substance that is being dissolved, while the solvent is the dissolving medium. Solutions can be formed with many different types and forms of solutes and solvents.


Solvent classifications

Solvents can be broadly classified into two categories: ''polar'' and ''non-polar''. A special case is
mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...
, whose solutions are known as
amalgams Amalgam most commonly refers to: * Amalgam (chemistry), mercury alloy * Amalgam (dentistry), material of silver tooth fillings ** Bonded amalgam, used in dentistry Amalgam may also refer to: * Amalgam Comics, a publisher * Amalgam Digital, an in ...
; also, other metal solutions exist which are liquid at room temperature. Generally, the
dielectric constant The relative permittivity (in older texts, dielectric constant) is the permittivity of a material expressed as a ratio with the electric permittivity of a vacuum. A dielectric is an insulating material, and the dielectric constant of an insulat ...
of the solvent provides a rough measure of a solvent's polarity. The strong polarity of water is indicated by its high dielectric constant of 88 (at 0 °C). Solvents with a dielectric constant of less than 15 are generally considered to be nonpolar.Lowery and Richardson, p. 177. The dielectric constant measures the solvent's tendency to partly cancel the field strength of the electric field of a
charged particle In physics, a charged particle is a particle with an electric charge. It may be an ion, such as a molecule or atom with a surplus or deficit of electrons relative to protons. It can also be an electron or a proton, or another elementary pa ...
immersed in it. This reduction is then compared to the
field strength In physics, field strength means the ''magnitude'' of a vector-valued field (e.g., in volts per meter, V/m, for an electric field ''E''). For example, an electromagnetic field results in both electric field strength and magnetic field strength ...
of the charged particle in a vacuum. Heuristically, the dielectric constant of a solvent can be thought of as its ability to reduce the solute's effective internal charge. Generally, the dielectric constant of a solvent is an acceptable predictor of the solvent's ability to dissolve common ionic compounds, such as salts.


Other polarity scales

Dielectric constants are not the only measure of polarity. Because solvents are used by chemists to carry out chemical reactions or observe chemical and biological phenomena, more specific measures of polarity are required. Most of these measures are sensitive to chemical structure. The '' Grunwald–Winstein mY scale'' measures polarity in terms of solvent influence on buildup of positive charge of a solute during a chemical reaction. '' Kosower's Z scale'' measures polarity in terms of the influence of the solvent on UV-absorption maxima of a salt, usually
pyridinium Pyridinium refers to the cation . It is the conjugate acid of pyridine. Many related cations are known involving substituted pyridines, e.g. picolines, lutidines, collidines. They are prepared by treating pyridine with acids. As pyridine is ...
iodide An iodide ion is the ion I−. Compounds with iodine in formal oxidation state −1 are called iodides. In everyday life, iodide is most commonly encountered as a component of iodized salt, which many governments mandate. Worldwide, iodine defic ...
or the pyridinium
zwitterion In chemistry, a zwitterion ( ; ), also called an inner salt or dipolar ion, is a molecule that contains an equal number of positively- and negatively-charged functional groups. : With amino acids, for example, in solution a chemical equilibrium wil ...
. ''Donor number and donor acceptor scale'' measures polarity in terms of how a solvent interacts with specific substances, like a strong
Lewis acid A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any sp ...
or a strong Lewis base. The '' Hildebrand parameter'' is the square root of cohesive energy density. It can be used with nonpolar compounds, but cannot accommodate complex chemistry. Reichardt's dye, a
solvatochromic In chemistry, solvatochromism is the phenomenon observed when the colour due to a solute is different when that solute is dissolved in different solvents. The solvatochromic effect is the way the spectrum of a substance (the solute) varies when th ...
dye that changes color in response to polarity, gives a scale of ''ET''(30) values. ''ET'' is the transition energy between the ground state and the lowest excited state in kcal/mol, and (30) identifies the dye. Another, roughly correlated scale (''ET''(33)) can be defined with
Nile red The Nile, , Bohairic , lg, Kiira , Nobiin: Áman Dawū is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa and has historically been considered the longest rive ...
. The polarity, dipole moment, polarizability and
hydrogen bonding In chemistry, a hydrogen bond (or H-bond) is a primarily electrostatic force of attraction between a hydrogen (H) atom which is covalently bound to a more electronegative "donor" atom or group (Dn), and another electronegative atom bearing a l ...
of a solvent determines what type of compounds it is able to dissolve and with what other solvents or liquid compounds it is
miscible Miscibility () is the property of two substances to mix in all proportions (that is, to fully dissolve in each other at any concentration), forming a homogeneous mixture (a solution). The term is most often applied to liquids but also applies ...
. Generally, polar solvents dissolve polar compounds best and non-polar solvents dissolve non-polar compounds best; hence "''like dissolves like''". Strongly polar compounds like
sugar Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose. Compound sugars, also called disaccharides or double ...
s (e.g.
sucrose Sucrose, a disaccharide, is a sugar composed of glucose and fructose subunits. It is produced naturally in plants and is the main constituent of white sugar. It has the molecular formula . For human consumption, sucrose is extracted and refined ...
) or ionic compounds, like
inorganic In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemist ...
salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...
s (e.g.
table salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...
) dissolve only in very polar solvents like water, while strongly non-polar compounds like
oil An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) & lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturated ...
s or
wax Waxes are a diverse class of organic compounds that are lipophilic, malleable solids near ambient temperatures. They include higher alkanes and lipids, typically with melting points above about 40 °C (104 °F), melting to giv ...
es dissolve only in very non-polar organic solvents like
hexane Hexane () is an organic compound, a straight-chain alkane with six carbon atoms and has the molecular formula C6H14. It is a colorless liquid, odorless when pure, and with boiling points approximately . It is widely used as a cheap, relatively ...
. Similarly, water and
hexane Hexane () is an organic compound, a straight-chain alkane with six carbon atoms and has the molecular formula C6H14. It is a colorless liquid, odorless when pure, and with boiling points approximately . It is widely used as a cheap, relatively ...
(or
vinegar Vinegar is an aqueous solution of acetic acid and trace compounds that may include flavorings. Vinegar typically contains 5–8% acetic acid by volume. Usually, the acetic acid is produced by a double fermentation, converting simple sugars to et ...
and vegetable oil) are not
miscible Miscibility () is the property of two substances to mix in all proportions (that is, to fully dissolve in each other at any concentration), forming a homogeneous mixture (a solution). The term is most often applied to liquids but also applies ...
with each other and will quickly separate into two layers even after being shaken well. Polarity can be separated to different contributions. For example, the Kamlet-Taft parameters are dipolarity/polarizability (''π*''), hydrogen-bonding acidity (''α'') and hydrogen-bonding basicity (''β''). These can be calculated from the wavelength shifts of 3–6 different solvatochromic dyes in the solvent, usually including Reichardt's dye, nitroaniline and diethylnitroaniline. Another option, Hansen's parameters, separate the cohesive energy density into dispersion, polar and hydrogen bonding contributions.


Polar protic and polar aprotic

Solvents with a dielectric constant (more accurately,
relative static permittivity The relative permittivity (in older texts, dielectric constant) is the permittivity of a material expressed as a ratio with the electric permittivity of a vacuum. A dielectric is an insulating material, and the dielectric constant of an insulat ...
) greater than 15 (i.e. polar or polarizable) can be further divided into
protic In chemistry, a protic solvent is a solvent that has a hydrogen atom bound to an oxygen (as in a hydroxyl group ), a nitrogen (as in an amine group or ), or fluoride (as in hydrogen fluoride). In general terms, any solvent that contains a labile ...
and aprotic. Protic solvents solvate
anion An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...
s (negatively charged solutes) strongly via
hydrogen bonding In chemistry, a hydrogen bond (or H-bond) is a primarily electrostatic force of attraction between a hydrogen (H) atom which is covalently bound to a more electronegative "donor" atom or group (Dn), and another electronegative atom bearing a l ...
. Water is a protic solvent. Aprotic solvents such as
acetone Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscib ...
or
dichloromethane Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour is widely used as a solvent. Although it is not miscible with ...
tend to have large dipole moments (separation of partial positive and partial negative charges within the same molecule) and solvate positively charged species via their negative dipole. In
chemical reaction A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the pos ...
s the use of polar protic solvents favors the SN1
reaction mechanism In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical change occurs. A chemical mechanism is a theoretical conjecture that tries to describe in detail what takes place at each stage of ...
, while polar aprotic solvents favor the SN2 reaction mechanism. These polar solvents are capable of forming hydrogen bonds with water to dissolve in water whereas non-polar solvents are not capable of strong hydrogen bonds.


Multicomponent solvents

Multicomponent solvents appeared after World War II in the USSR and continue to be used and produced in post-Soviet States. These solvents may have one or more applications, but they are not universal preparations.


Solvents


Thinners


Physical properties


Properties table of common solvents

The solvents are grouped into
nonpolar In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment, with a negatively charged end and a positively charged end. Polar molecules must contain one or more polar ...
, polar
aprotic A polar aprotic solvent is a solvent that lacks an acidic proton and is polar. Such solvents lack hydroxyl and amine groups. In contrast to protic solvents, these solvents do not serve as proton donors in hydrogen bonding In chemistry, a hydro ...
, and polar
protic In chemistry, a protic solvent is a solvent that has a hydrogen atom bound to an oxygen (as in a hydroxyl group ), a nitrogen (as in an amine group or ), or fluoride (as in hydrogen fluoride). In general terms, any solvent that contains a labile ...
solvents, with each group ordered by increasing polarity. The
properties Property is the ownership of land, resources, improvements or other tangible objects, or intellectual property. Property may also refer to: Mathematics * Property (mathematics) Philosophy and science * Property (philosophy), in philosophy and ...
of solvents which exceed those of water are bolded. The ACS Green Chemistry Institute maintains a tool for the selection of solvents based on a
principal component analysis Principal component analysis (PCA) is a popular technique for analyzing large datasets containing a high number of dimensions/features per observation, increasing the interpretability of data while preserving the maximum amount of information, and ...
of solvent properties.


Hansen solubility parameter values

The Hansen solubility parameter values are based on dispersion bonds (δD),
polar bonds In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment, with a negatively charged end and a positively charged end. Polar molecules must contain one or more pola ...
(δP) and
hydrogen bonds In chemistry, a hydrogen bond (or H-bond) is a primarily electrostatic force of attraction between a hydrogen (H) atom which is covalently bound to a more electronegative "donor" atom or group (Dn), and another electronegative atom bearing a ...
(δH). These contain information about the inter-molecular interactions with other solvents and also with polymers, pigments, nanoparticles, etc. This allows for rational formulations knowing, for example, that there is a good HSP match between a solvent and a polymer. Rational substitutions can also be made for "good" solvents (effective at dissolving the solute) that are "bad" (expensive or hazardous to health or the environment). The following table shows that the intuitions from "non-polar", "polar aprotic" and "polar protic" are put numerically – the "polar" molecules have higher levels of δP and the protic solvents have higher levels of δH. Because numerical values are used, comparisons can be made rationally by comparing numbers. For example, acetonitrile is much more polar than acetone but exhibits slightly less hydrogen bonding. If, for environmental or other reasons, a solvent or solvent blend is required to replace another of equivalent solvency, the substitution can be made on the basis of the
Hansen solubility parameters Hansen solubility parameters were developed by Charles M. Hansen in his Ph.D thesis in 1967 as a way of predicting if one material will dissolve in another and form a solution. They are based on the idea that like dissolves like where one molecul ...
of each. The values for mixtures are taken as the
weighted average The weighted arithmetic mean is similar to an ordinary arithmetic mean (the most common type of average), except that instead of each of the data points contributing equally to the final average, some data points contribute more than others. The ...
s of the values for the neat solvents. This can be calculated by
trial-and-error Trial and error is a fundamental method of problem-solving characterized by repeated, varied attempts which are continued until success, or until the practicer stops trying. According to W.H. Thorpe, the term was devised by C. Lloyd Morgan (1 ...
, a spreadsheet of values, or HSP software. A 1:1 mixture of
toluene Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon. It is a colorless, water-insoluble liquid with the smell associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) at ...
and 1,4 dioxane has δD, δP and δH values of 17.8, 1.6 and 5.5, comparable to those of
chloroform Chloroform, or trichloromethane, is an organic compound with chemical formula, formula Carbon, CHydrogen, HChlorine, Cl3 and a common organic solvent. It is a colorless, strong-smelling, dense liquid produced on a large scale as a precursor to ...
at 17.8, 3.1 and 5.7 respectively. Because of the health hazards associated with toluene itself, other mixtures of solvents may be found using a full HSP dataset.


Boiling point

The boiling point is an important property because it determines the speed of evaporation. Small amounts of low-boiling-point solvents like
diethyl ether Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liq ...
,
dichloromethane Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour is widely used as a solvent. Although it is not miscible with ...
, or acetone will evaporate in seconds at room temperature, while high-boiling-point solvents like water or
dimethyl sulfoxide Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula ( CH3)2. This colorless liquid is the sulfoxide most widely used commercially. It is an important polar aprotic solvent that dissolves both polar and nonpolar compounds a ...
need higher temperatures, an air flow, or the application of
vacuum A vacuum is a space devoid of matter. The word is derived from the Latin adjective ''vacuus'' for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often dis ...
for fast evaporation. *Low boilers: boiling point below 100 °C (boiling point of water) *Medium boilers: between 100 °C and 150 °C *High boilers: above 150 °C


Density

Most organic solvents have a lower
density Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' can also be used. Mathematical ...
than water, which means they are lighter than and will form a layer on top of water. Important exceptions are most of the
halogen The halogens () are a group in the periodic table consisting of five or six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts). In the modern IUPAC nomenclature, this group is ...
ated solvents like
dichloromethane Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour is widely used as a solvent. Although it is not miscible with ...
or
chloroform Chloroform, or trichloromethane, is an organic compound with chemical formula, formula Carbon, CHydrogen, HChlorine, Cl3 and a common organic solvent. It is a colorless, strong-smelling, dense liquid produced on a large scale as a precursor to ...
will sink to the bottom of a container, leaving water as the top layer. This is crucial to remember when partitioning compounds between solvents and water in a
separatory funnel A separatory funnel, also known as a separation funnel, separating funnel, or colloquially sep funnel, is a piece of laboratory glassware used in liquid-liquid extractions to separate (''partition'') the components of a mixture into two immisci ...
during chemical syntheses. Often,
specific gravity Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water (molecule), wa ...
is cited in place of density. Specific gravity is defined as the density of the solvent divided by the density of water at the same temperature. As such, specific gravity is a unitless value. It readily communicates whether a water-insoluble solvent will float (SG < 1.0) or sink (SG > 1.0) when mixed with water.


Safety


Fire

Most organic solvents are flammable or highly flammable, depending on their volatility. Exceptions are some chlorinated solvents like
dichloromethane Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour is widely used as a solvent. Although it is not miscible with ...
and
chloroform Chloroform, or trichloromethane, is an organic compound with chemical formula, formula Carbon, CHydrogen, HChlorine, Cl3 and a common organic solvent. It is a colorless, strong-smelling, dense liquid produced on a large scale as a precursor to ...
. Mixtures of solvent vapors and air can
explode An explosion is a rapid expansion in volume associated with an extreme outward release of energy, usually with the generation of high temperatures and release of high-pressure gases. Supersonic explosions created by high explosives are known ...
. Solvent vapors are heavier than air; they will sink to the bottom and can travel large distances nearly undiluted. Solvent vapors can also be found in supposedly empty drums and cans, posing a
flash fire A flash fire is a sudden, intense fire caused by ignition of a mixture of air and a dispersed flammable substance such as a solid (including dust), flammable or combustible liquid (such as an aerosol or fine mist), or a flammable gas. It is charact ...
hazard; hence empty containers of volatile solvents should be stored open and upside down. Both
diethyl ether Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liq ...
and
carbon disulfide Carbon disulfide (also spelled as carbon disulphide) is a neurotoxic, colorless, volatile liquid with the formula and structure . The compound is used frequently as a building block in organic chemistry as well as an industrial and chemical non ...
have exceptionally low
autoignition temperature The autoignition temperature or kindling point of a substance is the lowest temperature in which it spontaneously ignites in a normal atmosphere without an external source of ignition, such as a flame or spark. This temperature is required to su ...
s which increase greatly the fire risk associated with these solvents. The autoignition temperature of carbon disulfide is below 100 °C (212 °F), so objects such as
steam Steam is a substance containing water in the gas phase, and sometimes also an aerosol of liquid water droplets, or air. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization ...
pipes,
light bulb An electric light, lamp, or light bulb is an electrical component that produces light. It is the most common form of artificial lighting. Lamps usually have a base made of ceramic, metal, glass, or plastic, which secures the lamp in the soc ...
s,
hotplate A hot plate is a portable self-contained tabletop small appliance cooktop A cooktop (American English), stovetop (American English) or hob (British English), is a device commonly used for cooking that is commonly found in kitchens and used t ...
s, and recently extinguished
bunsen burner A Bunsen burner, named after Robert Bunsen, is a kind of ambient air gas burner used as laboratory equipment; it produces a single open gas flame, and is used for heating, sterilization, and combustion. The gas can be natural gas (which is main ...
s are able to ignite its vapours. In addition some solvents, such as methanol, can burn with a very hot flame which can be nearly invisible under some lighting conditions. This can delay or prevent the timely recognition of a dangerous fire, until flames spread to other materials.


Explosive peroxide formation

Ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be c ...
s like
diethyl ether Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liq ...
and
tetrahydrofuran Tetrahydrofuran (THF), or oxolane, is an organic compound with the formula (CH2)4O. The compound is classified as heterocyclic compound, specifically a cyclic ether. It is a colorless, water-miscible organic liquid with low viscosity. It is ma ...
(THF) can form highly explosive
organic peroxide In organic chemistry, organic peroxides are organic compounds containing the peroxide functional group (). If the R′ is hydrogen, the compounds are called hydroperoxides, which are discussed in that article. The O−O bond of peroxides easily b ...
s upon exposure to oxygen and light. THF is normally more likely to form such peroxides than diethyl ether. One of the most susceptible solvents is
diisopropyl ether Diisopropyl ether is secondary ether that is used as a solvent. It is a colorless liquid that is slightly soluble in water, but miscible with organic solvents. It is used as an extractant and an oxygenate gasoline additive. It is obtained indust ...
, but all ethers are considered to be potential peroxide sources. The heteroatom (
oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
) stabilizes the formation of a
free radical A daughter category of ''Ageing'', this category deals only with the biological aspects of ageing. Ageing Ailments of unknown cause Biogerontology Biological processes Causes of death Cellular processes Gerontology Life extension Metabo ...
which is formed by the abstraction of a
hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, an ...
atom by another free radical. The carbon-centred free radical thus formed is able to react with an oxygen molecule to form a peroxide compound. The process of peroxide formation is greatly accelerated by exposure to even low levels of light, but can proceed slowly even in dark conditions. Unless a
desiccant A desiccant is a hygroscopic substance that is used to induce or sustain a state of dryness (desiccation) in its vicinity; it is the opposite of a humectant. Commonly encountered pre-packaged desiccants are solids that absorb water. Desiccant ...
is used which can destroy the peroxides, they will concentrate during
distillation Distillation, or classical distillation, is the process of separation process, separating the components or substances from a liquid mixture by using selective boiling and condensation, usually inside an apparatus known as a still. Dry distilla ...
, due to their higher
boiling point The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor. The boiling point of a liquid varies depending upon the surrounding envir ...
. When sufficient peroxides have formed, they can form a
crystalline A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macrosc ...
, shock-sensitive solid
precipitate In an aqueous solution, precipitation is the process of transforming a dissolved substance into an insoluble solid from a super-saturated solution. The solid formed is called the precipitate. In case of an inorganic chemical reaction leading ...
at the mouth of a container or bottle. Minor mechanical disturbances, such as scraping the inside of a vessel or the dislodging of a deposit, merely twisting the cap may provide sufficient energy for the peroxide to explode or
detonate Detonation () is a type of combustion involving a supersonic exothermic front accelerating through a medium that eventually drives a shock front propagating directly in front of it. Detonations propagate supersonically through shock waves with s ...
. Peroxide formation is not a significant problem when fresh solvents are used up quickly; they are more of a problem in laboratories which may take years to finish a single bottle. Low-volume users should acquire only small amounts of peroxide-prone solvents, and dispose of old solvents on a regular periodic schedule. To avoid explosive peroxide formation, ethers should be stored in an airtight container, away from light, because both light and air can encourage peroxide formation. A number of tests can be used to detect the presence of a peroxide in an ether; one is to use a combination of
iron(II) sulfate Iron(II) sulfate (British English: iron(II) sulphate) or ferrous sulfate denotes a range of salts with the formula Fe SO4·''x''H2O. These compounds exist most commonly as the heptahydrate (''x'' = 7) but several values for x are know ...
and
potassium thiocyanate Potassium thiocyanate is the chemical compound with the molecular formula KSCN. It is an important salt of the thiocyanate anion, one of the pseudohalides. The compound has a low melting point relative to most other inorganic salts. Use in chem ...
. The peroxide is able to
oxidize Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a d ...
the Fe2+ ion to an Fe3+ ion, which then forms a deep-red
coordination complex A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many ...
with the
thiocyanate Thiocyanate (also known as rhodanide) is the anion . It is the conjugate base of thiocyanic acid. Common derivatives include the colourless salts potassium thiocyanate and sodium thiocyanate. Mercury(II) thiocyanate was formerly used in pyrot ...
. Peroxides may be removed by washing with acidic iron(II) sulfate, filtering through alumina, or
distilling Distillation, or classical distillation, is the process of separating the components or substances from a liquid mixture by using selective boiling and condensation, usually inside an apparatus known as a still. Dry distillation is the heat ...
from
sodium Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable iso ...
/
benzophenone Benzophenone is the organic compound with the formula (C6H5)2CO, generally abbreviated Ph2CO. It is a white solid that is soluble in organic solvents. Benzophenone is a widely used building block in organic chemistry, being the parent diarylket ...
. Alumina degrades the peroxides but some could remain intact in it, therefore it must be disposed of properly. The advantage of using sodium/benzophenone is that
moisture Moisture is the presence of a liquid, especially water, often in trace amounts. Small amounts of water may be found, for example, in the air (humidity), in foods, and in some commercial products. Moisture also refers to the amount of water vapo ...
and oxygen are removed as well.


Health effects

General health hazards associated with solvent exposure include toxicity to the nervous system, reproductive damage, liver and kidney damage, respiratory impairment, cancer, and
dermatitis Dermatitis is inflammation of the skin, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can v ...
.


Acute exposure

Many solvents can lead to a sudden loss of consciousness if
inhaled Inhalation (or Inspiration) happens when air or other gases enter the lungs. Inhalation of air Inhalation of air, as part of the cycle of breathing, is a vital process for all human life. The process is autonomic (though there are exceptions ...
in large amounts. Solvents like
diethyl ether Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liq ...
and
chloroform Chloroform, or trichloromethane, is an organic compound with chemical formula, formula Carbon, CHydrogen, HChlorine, Cl3 and a common organic solvent. It is a colorless, strong-smelling, dense liquid produced on a large scale as a precursor to ...
have been used in medicine as
anesthetics An anesthetic (American English) or anaesthetic (British English; see spelling differences) is a drug used to induce anesthesia ⁠— ⁠in other words, to result in a temporary loss of sensation or awareness. They may be divided into two ...
,
sedatives A sedative or tranquilliser is a substance that induces sedation by reducing irritability or excitement. They are CNS depressants and interact with brain activity causing its deceleration. Various kinds of sedatives can be distinguished, but th ...
, and
hypnotics Hypnotic (from Greek ''Hypnos'', sleep), or soporific drugs, commonly known as sleeping pills, are a class of (and umbrella term for) psychoactive drugs whose primary function is to induce sleep (or surgical anesthesiaWhen used in anesthesia ...
for a long time.
Ethanol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl ...
(grain alcohol) is a widely used and abused
psychoactive drug A psychoactive drug, psychopharmaceutical, psychoactive agent or psychotropic drug is a chemical substance, that changes functions of the nervous system, and results in alterations in perception, mood, consciousness, cognition or behavior. ...
. Diethyl ether, chloroform, and many other solvents e.g. from
gasoline Gasoline (; ) or petrol (; ) (see ) is a transparent, petroleum-derived flammable liquid that is used primarily as a fuel in most spark-ignited internal combustion engines (also known as petrol engines). It consists mostly of organic co ...
or glues are abused recreationally in glue sniffing, often with harmful long-term health effects like
neurotoxicity Neurotoxicity is a form of toxicity in which a biological, chemical, or physical agent produces an adverse effect on the structure or function of the central and/or peripheral nervous system. It occurs when exposure to a substance – specificall ...
or
cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...
. Fraudulent substitution of 1,5-pentanediol by the psychoactive
1,4-butanediol 1,4-Butanediol, colloquially known as BD or BDO, is a primary alcohol, and an organic compound, with the formula HOCH2CH2CH2CH2OH. It is a colorless viscous liquid. It is one of four stable isomers of butanediol. Synthesis In industrial sy ...
by a subcontractor caused the
Bindeez Bindeez (also marketed as Aqua Dots, Beados,Moose Beados Site PixOs,Pixos Site http://www.pixos.com/ and Aquabeads) are a children's toy, consisting of small coloured plastic beads that can be arranged in designs. In 2007, Bindeez was subjec ...
product recall. If ingested, the so-called toxic alcohols (other than ethanol) such as
methanol Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical and the simplest aliphatic alcohol, with the formula C H3 O H (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a ...
,
propanol There are two isomers of propanol. * 1-Propanol, ''n''-propanol, or propan-1-ol : CH3CH2CH2OH, the most common meaning *2-Propanol, Isopropyl alcohol, isopropanol, or propan-2-ol : (CH3)2CHOH See also * Propanal (propionaldehyde) differs in sp ...
, and
ethylene glycol Ethylene glycol (IUPAC name: ethane-1,2-diol) is an organic compound (a vicinal diol) with the formula . It is mainly used for two purposes, as a raw material in the manufacture of polyester fibers and for antifreeze formulations. It is an odo ...
metabolize into toxic aldehydes and acids, which cause potentially fatal
metabolic acidosis Metabolic acidosis is a serious electrolyte disorder characterized by an imbalance in the body's acid-base balance. Metabolic acidosis has three main root causes: increased acid production, loss of bicarbonate, and a reduced ability of the kidneys ...
. The commonly available alcohol solvent methanol can cause permanent blindness or death if ingested. The solvent 2-butoxyethanol, used in fracking fluids, can cause
hypotension Hypotension is low blood pressure. Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood. Blood pressure is indicated by two numbers, the systolic blood pressure (the top number) and the dias ...
and metabolic acidosis.


Chronic exposure

Some solvents including
chloroform Chloroform, or trichloromethane, is an organic compound with chemical formula, formula Carbon, CHydrogen, HChlorine, Cl3 and a common organic solvent. It is a colorless, strong-smelling, dense liquid produced on a large scale as a precursor to ...
and
benzene Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, ...
a common ingredient in gasoline are known to be
carcinogen A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of cancer). This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive substan ...
ic, while many others are considered by the
World Health Organization The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of h ...
to be likely carcinogens. Solvents can damage internal organs like the
liver The liver is a major Organ (anatomy), organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of proteins and biochemicals necessary for ...
, the
kidney The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blood ...
s, the
nervous system In biology, the nervous system is the highly complex part of an animal that coordinates its actions and sensory information by transmitting signals to and from different parts of its body. The nervous system detects environmental changes th ...
, or the
brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...
. The cumulative effects of long-term or repeated exposure to solvents are called
chronic solvent-induced encephalopathy Chronic solvent-induced encephalopathy (CSE) is a condition induced by long-term exposure to organic solvents, often - but not always - in the workplace, that lead to a wide variety of persisting sensorimotor polyneuropathies and neurobehavioral d ...
(CSE). Chronic exposure to organic solvents in the work environment can produce a range of adverse neuropsychiatric effects. For example, occupational exposure to organic solvents has been associated with higher numbers of painters suffering from
alcoholism Alcoholism is, broadly, any drinking of alcohol (drug), alcohol that results in significant Mental health, mental or physical health problems. Because there is disagreement on the definition of the word ''alcoholism'', it is not a recognize ...
. Ethanol has a
synergistic Synergy is an interaction or cooperation giving rise to a whole that is greater than the simple sum of its parts. The term ''synergy'' comes from the Attic Greek word συνεργία ' from ', , meaning "working together". History In Christi ...
effect when taken in combination with many solvents; for instance, a combination of
toluene Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon. It is a colorless, water-insoluble liquid with the smell associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) at ...
/
benzene Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, ...
and ethanol causes greater
nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...
/
vomiting Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the Human nose, nose. Vomiting can be the result of ailments like Food-poisoning, foo ...
than either substance alone. Many solvents are known or suspected to be cataractogenic, greatly increasing the risk of developing
cataract A cataract is a cloudy area in the lens of the eye that leads to a decrease in vision. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colors, blurry or double vision, halos around light, trouble w ...
s in the lens of the eye. Solvent exposure has also been associated with neurotoxic damage causing
hearing loss Hearing loss is a partial or total inability to Hearing, hear. Hearing loss may be present at birth or acquired at any time afterwards. Hearing loss may occur in one or both ears. In children, hearing problems can affect the ability to Language ...
and
color vision Color vision, a feature of visual perception, is an ability to perceive differences between light composed of different wavelengths (i.e., different spectral power distributions) independently of light intensity. Color perception is a part of ...
losses.


Environmental contamination

A major pathway to induce health effects arises from spills or leaks of solvents that reach the underlying soil. Since solvents readily migrate substantial distances, the creation of widespread
soil contamination Soil contamination, soil pollution, or land pollution as a part of land degradation is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activity ...
is not uncommon; this is particularly a health risk if
aquifer An aquifer is an underground layer of water-bearing, permeable rock, rock fractures, or unconsolidated materials (gravel, sand, or silt). Groundwater from aquifers can be extracted using a water well. Aquifers vary greatly in their characterist ...
s are affected.
Vapor intrusion Vapor intrusion (VI) is a process by which chemicals in soil or groundwater - especially Volatile Organic Compounds (VOCs) - migrate to indoor air above a contaminated site. Definition The United States Environmental Protection Agency defines va ...
can occur from sites with extensive subsurface solvent contamination.


See also

* Free energy of solvation * Solvents are often refluxed with an appropriate
desiccant A desiccant is a hygroscopic substance that is used to induce or sustain a state of dryness (desiccation) in its vicinity; it is the opposite of a humectant. Commonly encountered pre-packaged desiccants are solids that absorb water. Desiccant ...
prior to distillation to remove water. This may be performed prior to a chemical synthesis where water may interfere with the intended reaction * List of water-miscible solvents *
Lyoluminescence Lyoluminescence refers to the emission of light while dissolving a solid into a liquid solvent. It is a form of chemiluminescence. The most common lyoluminescent effect is seen when solid samples which have been heavily irradiated by ionizing radia ...
*
Occupational health Occupational safety and health (OSH), also commonly referred to as occupational health and safety (OHS), occupational health, or occupational safety, is a multidisciplinary field concerned with the safety, health, and welfare of people at wor ...
*
Partition coefficient In the physical sciences, a partition coefficient (''P'') or distribution coefficient (''D'') is the ratio of concentrations of a compound in a mixture of two immiscible solvents at equilibrium. This ratio is therefore a comparison of the solub ...
(log ''P'') is a measure of differential solubility of a compound in two solvents *
Solvation Solvation (or dissolution) describes the interaction of a solvent with dissolved molecules. Both ionized and uncharged molecules interact strongly with a solvent, and the strength and nature of this interaction influence many properties of the ...
* Solvent systems exist outside the realm of ordinary organic solvents:
Supercritical fluid A supercritical fluid (SCF) is any substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist, but below the pressure required to compress it into a solid. It can effuse through porous so ...
s,
ionic liquid An ionic liquid (IL) is a salt in the liquid state. In some contexts, the term has been restricted to salts whose melting point is below a specific temperature, such as . While ordinary liquids such as water and gasoline are predominantly made of ...
s and
deep eutectic solvent Deep eutectic solvents or DESs are solutions of Lewis or Brønsted acids and bases which form a eutectic mixture. Deep eutectic solvents are highly tunable through varying the structure or relative ratio of parent components and thus have a wide va ...
s *
Water model In computational chemistry, a water model is used to simulate and thermodynamically calculate water clusters, liquid water, and aqueous solutions with explicit solvent. The models are determined from quantum mechanics, molecular mechanics, experim ...
*
Water pollution Water pollution (or aquatic pollution) is the contamination of water bodies, usually as a result of human activities, so that it negatively affects its uses. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. Water ...


References


Bibliography

*


External links


Solvent selection tool
ACS Green Chemistry Institute
"European Solvents Industry Group - ESIG - ESIG European Solvents Industry Group"
Solvents in Europe.

O-Chem Lecture

Properties and toxicities of organic solvents
CDC – Organic Solvents – NIOSH Workplace Safety and Health TopicEPA – Solvent Contaminated Wipes
{{Authority control Soil contamination Solutions Chemical compounds he:תמיסה#הממס