Introduction to Atomic Structure

Subatomic Particles

• Protons: Positively charged particles ($+1$) found in the nucleus with a relative mass of $1$.
• Neutrons: Electrically neutral particles ($0$) found in the nucleus with a relative mass of $1$.
• Electrons: Negatively charged particles ($-1$) that orbit the nucleus in shells with a negligible relative mass (approximately $\frac{1}{1840}$).

Atomic Identifiers

• Atomic Number ($Z$): The number of protons in the nucleus of an atom, which uniquely identifies the element.
• Mass Number ($A$): The total number of protons and neutrons in the nucleus.
• Isotope: Atoms of the same element that have the same number of protons ($Z$) but a different number of neutrons, resulting in different mass numbers ($A$).

Atomic Charge and Stability

• Neutral Atom: An atom where the number of protons equals the number of electrons, resulting in a net charge of $0$.
• Nucleus: The small, dense center of the atom containing the majority of its mass.

Questions & Discussion

• Question: Can you help me with learning the atomic structure?
• Response: This summary provides the fundamental constituents (protons, neutrons, electrons) and the primary methods for identifying atoms using atomic and mass numbers.