What is an atom?
it is the smallest unit in matter, it contains all the chemical elements of the element, and it is composed of a nucleus of positively charged protons, moderately charged neutrons, and negatively charged electrons, all of which revolve around the nucleus, and the size of the atom depends on the number of protons and neutrons that make up it, and if It contains electrons, and the size of a typical atom is about 0.1 nanometer, and most of its size is an empty space, which is where the electrons are located, and small atoms are usually similar in shape, so that they are spherical.
Ingredients of atom:
it consists of two regions, which are the small atomic nucleus, which is the center of the atom, which contains protons and neutrons, and a region that forms a cloud of electrons orbiting the nucleus, which is much larger than the atom, and most atoms contain these three particles, except for the hydrogen element, it contains a proton One and one electron and there are no neutrons in it.
The basic properties :
1. Atomic number: The atomic number refers to the number of positively charged units, which are the protons in the nucleus, and the neutral atom contains an equal number of protons and electrons, so that the positive and negative charges balance together, and the number of protons in the nucleus determines the chemical properties of the atom , Whereas the electrons determine how the atom interacts with other atoms.
2- Atomic mass and isotopes:The number of neutrons in the nucleus affects the mass , and does not affect its chemical properties, so if the nucleus contains six protons and six neutrons, then it is similar in properties that contains six protons and eight neutrons, but differs in their mass, and it is believed that the nuclei that contain The same number of protons, but different number of neutrons, are isotopes of each other, and all chemical elements have many isotopes.