How to define an atom charge

How to define an atom charge

The atom charge, along with its quantum numbers, is one of the most important numerical characteristics of atom. Knowledge of a charge of atom is necessary for the solution of various problems of an electrostatics, electrodynamics, atomic and nuclear physics.

It is required to you

  • Knowledge of structure of atom, atomic number


1. Atom of any substance consists of an electron shell and a kernel. The kernel consists of two types of particles - neutrons and protons. Neutrons have no electric charge, that is electric charge of neutrons is not equal to zero. Protons are positively charged particles and have the electric charge equal +1. The quantity of protons characterizes atomic number of this atom. The electron shell of a kernel consists of electronic orbitals on which the different quantity of electrons is located. An electron - a negatively charged elementary particle. Its electric charge is equal to-1.

2. To define an atom charge, it is necessary to know its structure - quantity of protons in a kernel and quantity of electrons in an electron shell. The total charge of atom turns out as a result of algebraic summation of charges of the protons and electrons entering it. As a rule, atom is electroneutral, that is the quantity of protons is equal in it to quantity of electrons. The charge of such atom, obviously, is equal to zero. The example - atom of hydrogen H consists of one proton and one electron. Q = 1+(-1) = 0 - a charge of electroneutral hydrogen.

3. Owing to some reasons the quantity of protons and electrons in atom can not coincide. In this case atom is positively or a negatively charged ion. For example, the positive ion of sodium has 11 protons and 10 electrons. Its charge Q = 11+(-10) = 1.

Author: «MirrorInfo» Dream Team