Structure of an Atom

Structure of an Atom

• Atoms are tiny particles too small to be seen with the naked eye. They consist of even smaller particles called subatomic particles.
• Atoms are made up of a central nucleus surrounded by orbiting electrons.
• The nucleus contains protons and neutrons. Protons have a positive charge, and neutrons have no charge. This makes the nucleus overall positively charged.
• Electrons have a negative charge and orbit the nucleus due to electrostatic attraction.
• The arrangement of these particles is similar to planets orbiting the sun, with the nucleus acting like the sun and the electrons acting like the planets.

Mass and Size of an Atom

• Protons and neutrons have roughly the same mass, while electrons are significantly lighter (2,000 times lighter).
• The majority of an atom's mass is concentrated in its nucleus, containing the protons and neutrons.
• The radius of an atom is measured from the center of the nucleus to the outermost electron shell, typically around 10^-10 meters.
• The nucleus is much smaller than the entire atom, even though it contains most of the mass. It's like comparing a sports arena to a single "p" in the middle of the arena.

Electron Shells and Energy Levels

• Electrons orbit the nucleus in specific shells or orbitals, each representing a distinct energy level.
• Electrons closer to the nucleus have lower energy levels, while those farther away have higher energy levels.
• This is similar to planets orbiting the sun, but electrons can only occupy specific orbits with specific energy levels.
• The energy levels are quantized, meaning electrons can only exist at specific energy levels determined by their distance from the nucleus.