What is an atom?
The word "Atom" has several meanings. Basically, it is used in chemistry and physics to designate the smallest indivisible particle from which the molecules of the most diverse substances are composed. Atoms have microscopic masses and sizes, they are not distinguishable without special equipment and act as the main carrier of the properties of any substance.
What is an atom and what properties does it have?
Man for many centuries was interested instructure of the universe and all objects surrounding it. After achieving a certain level of technological progress, the creation of electron microscopes and other high-precision equipment, it was possible to prove that the atom is the smallest particle from which any substances consist. Despite this, there are many theories that suggest the existence of smaller particles that science is not yet able to identify due to imperfections in existing technologies.
The atom itself consists of electrons and an atomic nucleus(which is about 99.9% of its mass). In those cases when the number of electrons on the orbits of an atom corresponds to the number of protons (positively charged particles) inside its nucleus, it has a neutral electric effect. Otherwise, if the volume of certain particles is more or less, it will have a positive or negative charge and will become known as an ion.
Atoms of various types, which are connected with each other by means of interatomic bonds, constitute molecules of any substance.
More details about molecules you can find in the article What is a molecule.