In life, we are surrounded by a variety of bodies and objects. For example, indoors it is a window, a door, a table, a light bulb, a cup, on the street - a car, a traffic light, asph alt. Any body or object is made up of matter. This article will discuss what a substance is.
What is chemistry?
This is the science of nature, studying organic and inorganic substances, their structure, properties and transformations as a result of chemical reactions. Chemistry belongs to one of the vast areas of natural science and deals with 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 importance of chemistry in human life
Minerals, living organisms, rocks and the atmosphere are composed of different ratios of the same elements. The main difference between animate and inanimate nature is which molecules were formed from certain chemical elements. The basis of the vital activity of our biosphere will becycle of chemical elements.
Human life is impossible without industrial goods (food, vitamins, medicines, cosmetics, artificial fibers, building materials, various varnishes and paints, mineral fertilizers, and much more).
Molecules and atoms
All substances are made up of very small particles called molecules (from Latin - mass). All molecules are made up of even more microscopic particles - atoms, or rather, nuclei, which are surrounded by internal and external electrons that form chemical bonds. Atoms have a certain mass, so the composition of matter is constant. The main features of the structure of the molecule were discovered in the course of scientific research on chemical reactions, the analysis of chemical compounds and the application of physical methods. Atoms in molecules are connected by chemical bonds. Microscopic particles in a molecule can be either positively or negatively charged.
The concept of matter
What is a substance? Substance is considered to be that of which all bodies and objects in the surrounding nature consist. All substances contain molecules, and molecules, in turn, consist of atoms. For example, an iron nail will be a body, and iron will be a substance. Any substance has a certain set of physical and chemical properties.
Physical characteristics include features that distinguish one substance from another. These include: aggregatecondition, density, solubility, color, luster, temperature (boiling or melting point), electrical conductivity.
Chemical properties - the properties of substances to react and manifest themselves in chemical processes (reactions).
The task of chemistry is to get acquainted with the physical and chemical properties of matter.
Varieties of substances
There are classes of substances that are simple and complex. Simple substances are substances that consist of atoms of one chemical element. For example, molecules of inert gases (neon, argon, oxygen, bromine, iodine). Complex substances include all substances that were formed due to the combination of various atoms (water, table s alt, carbon dioxide, potassium permanganate, sucrose). Active substances - substances in chemical reactions that can reduce surface tension when concentrated on the surface.
Organic matter
This category includes all substances that contain carbon. Exceptions are carbides, carbon oxides, carbonates and carbon-containing cyanides and gases.
The saccharide substance molecule consists of three elements and is the main source of energy for living organisms. Monosaccharides are compounds that do not undergo crystallization. Oligosaccharides (sucrose, lactose, m altose) consist of two, three or four monosaccharide molecules. subjected to crystallization. Polysaccharides (glycogen, starch, arabans, xylans) are unsweetened in taste and do not dissolve in water. Their main function isconnection, gluing and binding of cells. Lipids are a group of compounds found in all living cells. They look like simple carbon chains or remnants of cyclic molecules. They are divided into fats (triglycerides and neutral) and lipoids. These are difficult ethers. Fatty acids (stearic, ricin) 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 processes of a protein nature. 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 and stabilizer. It has strong heat capacity and thermal conductivity. The aquatic environment is favorable for the occurrence of basic chemical reactions. It is translucent and virtually compression resistant.
Nitrogen is a part of many non-protein compounds. Sulfur takes an active part in their construction. Most living organisms contain phosphorus in 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 takes an active part in the processes of respiration, photosynthesis and is a component of hemoglobin. In the dieta person receives 2 mg of copper every day. Its deficiency reveals anemia, impaired appetite and heart disease. Manganese affects the renewal processes in plants. Zinc breaks down carbonic acid. Boron affects the growth of various organisms. In its absence in the soil, flowers and conducting channels die off in plants. Molybdenum actively destroys parasites and has gained wide popularity in crop production.
What is the difference between inorganic and organic substances?
There are no particularly strong external differences between these two groups of substances. The main difference lies in the structure, where inorganic substances have a non-molecular structure, and organic substances have a molecular structure.
Inorganic substances have a non-molecular structure, so 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, s alts.
Organic substances of molecular structure. They have fairly low melting points and decompose rapidly when heated. Mostly composed of carbon. Exceptions: carbides, carbonates, oxides of carbon and cyanides. Carbon allows the formation of a huge number of complex compounds (more than 10 million are known in nature).
Most of their classes belong to biological origin (carbohydrates, proteins, lipids, nucleic acids). These compounds include nitrogen, hydrogen, oxygen, phosphorus and sulfur.
To understand what a substance is, you need to imagine 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 made up of certain substances, so they play an important role in our lives.
