Every time two atoms join together, they form a molecule. In fact, everything that surrounds us – and we ourselves – is made up of trillions of different types of molecules. The concept of a molecule was made in 1860, at the international Congress of chemists in Karlsruhe. According to the definition of a molecule is the smallest particle of a chemical substance that has all its chemical properties (solubility, taste, ability to engage in connection, etc.). The introduction of the concept of molecules has driven the development of physics, chemistry and other natural Sciences. In a more General understanding of molecule called a particle formed of two or more atoms interconnected by covalent bonds.
When atoms of different types of elements bonded together, they form molecules called compounds. So, water is composed of complex molecules consisting of 2 hydrogen atoms and 1 oxygen atom. That’s why it’s called H2O: the water molecules is always 2 times more hydrogen atoms than oxygen atoms. There is a little more than 100 types of atoms, but different types of substances millions. The reason for this inequality lies in the fact that they consist of different types of molecules.
It is important to understand that the molecules consist not only of different types of atoms, but of different proportions. As in the example above, with water, water molecule consists of two hydrogen atoms and one oxygen atom that is written as H2O. Other examples are carbon dioxide (C02), ammonia (NH3) and sugar or glucose (C6H12O6). Some molecular formulas can be quite long and complex. Let’s look at a sugar molecule:
- C6 — 6 carbon atoms
- H12 — 12 atoms of hydrogen
- The oxygen atom O6 — 6
So it happened we need certain atoms in a certain amount. But molecules can be much more. One molecule of vitamin C consists of 20 atoms (6 carbons, 8 hydrogen atoms and 6 oxygen atoms – C6H8O6). If you take those 20 atoms of vitamin C and mix, joining them together in a different order, you get a totally different molecule that not only looks different, but acts differently.
Some molecules, especially certain proteins, contain hundreds or even thousands of atoms that are joined together in chains that can attain considerable lengths. Fluids containing such molecules, sometimes acting weird. For example, the fluid may continue to leak from the flask, which was poured some of it, even after the flask is returned to vertical position.
Facts about molecules
- Gaseous oxygen is usually a molecule of O2, but it may be O3, which we call ozone.
- Molecules can have different shapes. Some are long spirals while others may have a pyramid shape.
- Perfect diamond is a single molecule composed of carbon atoms.
- DNA is very long molecule that has the information describing each person.
- 66% of the mass of the human body consists of oxygen atoms
Molecules and compounds are held together by forces called chemical bonds. There are four types of chemical bonds, which hold the most connections together: covalent bonds, ionic bonds, hydrogen and metallic, but as the main distinguish covalent and ionic, as they are associated with electrons. As is known, the electrons revolve around the atom in shells. These shell want to be “full” of electrons. When they are not filled, it will try to connect with other atoms to obtain the necessary number of electrons to fill their shells.
Covalent bonds share electrons between atoms. This happens when it turns out that the atoms share their electrons to fill their outer shell. In turn, ionic bonds are formed when one electron is transferred to another. This occurs when one atom gives an electron to another to form a balance and thus the molecule or compound.