What is an atom and a molecule?

Every day we use any objects: we take them in hand, we make any manipulations on them - we turn them over, we look, in the end, we break them. Have you ever thought about what these items consist of? "What is there to think about? From metal / wood / plastic / fabric!" - Many of us will answer in perplexity. In part this is the right answer. And what do these materials consist of - metal, wood, plastic, fabric and many other substances? Today we will discuss this issue.

Molecule and atom: definition

At the knowing person the answer to it is simple and banal: from atoms and molecules. But some people are puzzled and begin to pour out questions: "What is an atom and a molecule, how do they look?" etc. We will answer these questions in order. Well, first, what is an atom and a molecule? Let us tell you at once that these definitions are not the same thing. And even more so - these are completely different terms. So, an atom is the smallest part of a chemical element that is the carrier of its properties, a particle of a substance of scanty mass and size. A molecule is an electrically neutral particle, which is formed by several atoms connected by covalent bonds .

What is an atom: a structure

The atom consists of an electron shell and an atomic nucleus (photo). In turn, the core consists of protons and neutrons, and the shell - of electrons. In the atom, the protons are positively charged, the electrons negatively, and the neutrons are not charged at all. If the number of protons corresponds to the number of electrons, then the atom is electrically neutral, i.e. If we touch a substance formed from molecules with such atoms, then we will not feel the slightest electric impulse. And even super-power computers will not catch it because of the absence of the latter. But it happens that there are more protons than electrons, and vice versa. Then such atoms will be more correctly called ions. If it has more protons, then it is electrically positive, but if electrons predominate, it is electrically negative. In each particular atom there is a strict number of protons, neutrons and electrons. And it can be calculated. The template for solving the problems of finding the number of these particles is as follows:

Chem. Element - R (insert the name of the element)
The Protons (p) -?
Electrons (e) -?
Neutrons (n) -?
Decision:
P = ordinal no. Element R in the periodic system of D.I. Mendeleyev's
E = p
N = A _r (R) - No. R

What is a molecule: a structure

A molecule is the smallest particle of a chemical substance, that is, it already directly enters into its composition. A molecule of a certain substance consists of several identical or different atoms. The peculiarities of the structure of molecules depend on the physical properties of the substance in which they are present. Molecules consist of electrons and atoms. The location of the latter can be found using the structural formula. The structure of the molecule makes it possible to determine the course of the chemical reaction. Usually they are neutral (they do not have an electric charge), and they do not have unpaired electrons (all valences are saturated). However, they can also be charged, then their correct name is ions. Also, molecules can have unpaired electrons and unsaturated valences - in this case they are called radicals.

Conclusion

Now you know what an atom is and what a molecule is. All without exception substances consist of molecules, and the latter, in turn, are constructed of atoms. The physical properties of matter determine the location and connection of atoms and molecules in it.