In life, we are surrounded by a variety of bodies anditems. For example, in rooms it is a window, a door, a table, a light bulb, a cup, on the street - a car, a traffic light, asphalt. Any bodies or objects consist of a substance. In this article we will talk about what a substance.
What is chemistry?
This is the science of nature, studying organic andinorganic substances, their structure, properties and transformations as a result of chemical reactions. Chemistry belongs to one of the vast areas of natural science and is engaged in the study of interactions between molecules and atoms. It gives a clear concept of what a substance is, and is very closely interconnected with physics and biology, and therefore belongs to the natural sciences.
The value of chemistry in human life
Minerals, living organisms, rocks andThe atmosphere consists of a different ratio of the same elements. The main difference between animate and inanimate nature is which molecules are formed from certain chemical elements. The basis of the life of our biosphere will be the cycle of chemical elements.
Human life is impossible without goodsindustries (food, vitamins, medicines, cosmetic substances, artificial fibers, building materials, various varnishes and paints, mineral fertilizers, and much more).
Molecules and Atoms
Any substances consist of very small particles,called molecules (from Latin - mass). All molecules are made up of even more microscopic particles — atoms, more precisely, of nuclei, which are surrounded by internal and external electrons that form chemical bonds. Atoms have a certain mass, so the composition of the substance is constant. The main features of the structure of the molecule were found in the course of scientific research of chemical reactions, analysis of chemical compounds and the use of physical methods. Atoms in molecules are connected by chemical bonds. Microscopic particles in a molecule can be both positively and negatively charged.
Concept of substance
Что такое вещество?The substance is considered to be what consists of all the bodies and objects in the surrounding nature. Any substances contain molecules, and molecules, in turn, consist of atoms. For example, an iron nail will be a body, and an iron will be a substance. Any substances have a certain set of physical and chemical properties.
Physical characteristics includesigns that distinguish some substances from others. These include: state of aggregation, density, solubility, color, gloss, temperature (boiling or melting), electrical conductivity.
Chemical properties - the properties of substances to react and manifest themselves in chemical processes (reactions).
The task of chemistry is familiarity with the physical and chemical properties of a substance.
Varieties of substances
There are classes of substances that бывают простыми и сложными.The simple ones include substances that consist of atoms of one chemical element. For example, inert gas molecules (neon, argon, oxygen, bromine, iodine). All substances that were formed due to the combination of various atoms (water, salt, carbon dioxide, potassium permanganate, sucrose) can be considered as complex. Active substances - substances in chemical reactions that can reduce surface tension at a concentration on the surface.
Organic matter
This category includes all substances that contain carbon. The exceptions are carbides, carbon oxides, carbonates, and carbon-containing cyanides and gases.
The molecule of a saccharide substance consists of threeelements and is the main source of energy for living organisms. Monosaccharides are compounds that do not undergo crystallization. Oligosaccharides (sucrose, lactose, maltose) consist of two, three or four molecules of monosaccharides. Crystallize. Polysaccharides (glycogen, starch, arabanes, xylans) are savory and do not dissolve in water. Their main function - the connection, bonding and binding of cells. Lipids include a group of compounds contained in all living cells. They look like simple carbon chains or residues of cyclic molecules. They are divided into fats (triglycerides and neutral) and lipids. This is not easy ethers. Fatty acids (stearic, ricinic) are also found in living organisms. Lipoids are fat-like substances that are important due to their structure. They form clearly oriented layers. Enzymes include active biological accelerators of protein processes. They are not destroyed by reactions and differ from chemical catalysts in that they are able to increase the reaction rate under normal conditions.
Inorganic substances
Inorganic substances include: water, oxygen, carbon, hydrogen, nitrogen, potassium, calcium, sodium, phosphorus, sulfur.
Water is an indispensable solvent andstabilizer. It has a strong heat capacity and thermal conductivity. The aqueous medium is favorable for the course of basic chemical reactions. It is characterized by transparency and is practically resistant to compression.
Many non-protein compounds include nitrogen.Sulfur takes an active part in their construction. Most living organisms contain phosphorus in the mineral form. Potassium is found in cells in the form of ions. It activates the balance of protein enzymes. Sodium is part of the blood and plays a major role in regulating the water balance of the whole organism. Iron is actively involved in the processes of respiration, photosynthesis and is a component of hemoglobin. In the human diet every day comes 2 mg of copper. Its deficiency reveals anemia, anorexia and heart disease. Manganese affects the renewal processes in plants. Zinc breaks down carbonic acid. Boron affects the growth of various organisms. In the absence of it in the soil in plants, flowers and conducting channels die off. Molybdenum is actively destroying parasites and has gained wide popularity in plant growing.
What is the difference between inorganic and organic substances?
The particularly strong external differences between these twothere are no groups of substances. The main difference is in the structure, where inorganic substances have a non-molecular structure, and organic - molecular.
Неорганические вещества имеют немолекулярное structure, therefore, they are characterized by high melting and boiling points. They do not contain carbon. These include noble gases (neon, argon), metals (calcium, calcium, sodium), amphoteric substances (iron, aluminum) and non-metals (silicon), hydroxides, binary compounds, salts.
Organic substances of molecular structure.They have rather low melting points, and they quickly decompose when heated. Mainly composed of carbon. Exceptions: carbides, carbonates, carbon oxides, and cyanides. Carbon allows you to form a huge number of complex compounds (in nature, they know more than 10 million).
Most of their classes belong to biological birth (carbohydrates, proteins, lipids, nucleic acids). These compounds include nitrogen, hydrogen, oxygen, phosphorus and sulfur.
To understand what a substance is, it is necessaryimagine what role it plays in our lives. Interacting with other substances, it forms new ones. Without them, the vital activity of the surrounding world is inseparable and unthinkable. All objects are composed of certain substances, so they play an important role in our lives.
