Define Atomic structure, atomic number, atomic mass number

Atomic structure:

• Atoms are made up of three types of subatomic particles: protons, neutrons, and electrons.
• The nucleus, located at the center of the atom, contains protons and neutrons, while electrons orbit the nucleus in shells or energy levels.
• The arrangement of electrons in an atom's energy levels determines its chemical properties and behavior.

Atomic number:

• Atomic number is the number of protons in the nucleus of an atom.
• The atomic number determines the element to which an atom belongs.
• Elements with the same atomic number have similar chemical properties.

Atomic mass number:

• Atomic mass number is the total number of protons and neutrons in the nucleus of an atom.
• Isotopes of the same element have the same atomic number but different atomic mass numbers.
• The atomic mass of an element listed on the periodic table is an average of the atomic masses of all its isotopes, weighted by their relative abundances.