Every type of atom has its own special structure. This is because of the number and arrangement of three tiny particles: protons, neutrons, and electrons.

• Protons: These are important because they tell us the atomic number and what element it is.
• Neutrons: These help decide the isotope and the atomic mass of the atom.
• Electrons: These affect how the atom behaves chemically and how it bonds with other atoms.

When you put these particles together, they create different properties. For example, sodium reacts with water, but chlorine does not.

It’s really interesting how such small changes can lead to such different behaviors!