Atomic Structure

Every element is composed of tiny particles called atoms. These particles give each element distinct physical and chemical properties, such as boiling point, melting point, and density.

All of the atoms of an element have identical properties but differ from those of other elements.

Such differences are due to the subatomic particles—protons, neutrons, and electrons.

Both protons and neutrons contribute to the atomic mass, with one atomic mass unit each, while electrons have almost negligible mass.

Protons and neutrons are clustered in a central nucleus. The number of protons, equal to the atomic number, determines the specific element.

Protons are positively charged, and neutrons are uncharged, so the nucleus has a net positive charge.

A cloud of negatively charged electrons is attracted to the nucleus. This cloud is mostly empty and makes up most of an atom's volume.

A neutral atom contains an equal number of protons and electrons, canceling out the positive and negative charges and leading to no net charge.