Non-polar solvents and their opponents in the service of man

What is a solvent?

In daily life, all humanity every day use solvents.Some may disagree with this statement, insisting that all special formulations capable of dissolving various substances, and people use them only from time to time as needed.

In some ways, these dissenters are right, solvents - it's really the chemical organic and inorganic compounds that are functionally capable of dissolving various substances.But the most well-known and common type of such substances is water, which mankind uses in a daily process of life, and which covers 70% of the surface of our planet.

And thousands of scientists around the world are trying to find life in the universe, based on the presence of water on one or another planet.Agree, it sounds pretty strange - the basis of life on the planet is a solvent.

Like all chemical compounds of this class can be divided into organic and inorganic.If classified by their physical properties, they are low-boiling (t boiling below 100 ° C) and high boiling (t boiling above 150 ° C).They are also distinguished by the degree of volatility: nonvolatile, of moderately and highly volatile.Depending on the degree of the viscosity of these compounds are low viscosity, middle viscosity and high viscosity.

addition, the treated substance and the presence / absence of a dipole moment, and the value of dielectric permittivity.According to these indicators are polar and non-polar solvents .

polar and non-polar solvents - consider the nature of the substances

polar solvents - are chemical compounds, which is a molecule dipole.All polar representatives in its molecule have donor atoms, but are divided into the containing mobile protons or proton (water, carboxylic acids, amines) and containing no such protons another name aprotic (ketones, ethers and tertiary amines).

The advantages of polar solvents include:

• ability to form hydrogen bonds;
• content of acidic protons;
• ability to stabilize the ions: cations - at the expense of the lone pair of electrons;anions - obtained by hydrogen bonds.
• high dielectric constant;
• ability to dissolve a variety of polar organic substances;
• a wide temperature range of the liquid state.

most well-known and frequently used representatives of this class are water, methyl alcohol, glycerol.

non-polar substance - this connection, a molecule which is not a dipole.They do not dissolve the salts and bases, often acting in reactions nucleotide reagents.Therefore, in such cases, these solvents are used rarely.Also they have low boiling point, which prevents their use in reactions with thermal excitation of molecules.

non-polar mixture perfectly dissolved nonpolar gas molecules.This feature is widely used for compressed gases, the structure of which is extremely unstable and dangerous, but they are well dissolved transported and stored in steel cylinders.The best known of this class of solvents - is acetone, white spirit, benzene.

Applications solvents

From all written above it can be concluded that the polarity of the solvent plays a very important role in determining their properties.There is an unwritten rule the use of these solvents, "like dissolves like", which accurately characterizes their field of application.

Hydrocarbon solvents (non-polar) are widely used in the paint industry, thanks to the low cost and wide availability.They are obtained by the distillation of shale gasoline, gas oil, crude oil and coal.

Ketones (polar) are also used in the paint industry, due to the high solvent power and relatively low toxicity.Esters of - the most common type of organic solvent to affect the polymers in the coatings industry, in medicine.

alcohols are used in a process solvent, cleaner surfaces, in the manufacture of consumer products, aerosol solvents, etc.

Almost all the organic solvents are toxic, and exert harmful effects on humans.At work with them it is necessary to strictly adhere to safety measures.The premises where the work carried out, must be well ventilated, and do the necessary manipulations performed with gloves and respirators.

also need to take into account the exceptional fire risk compounds.So where are stored these components is necessary to observe fire safety rules.