Inside the Atom
Atoms, the basic units of matter, consist of protons, neutrons, and electrons, and understanding atomic structure explains chemical behaviou
Core concept
Protons, positively charged particles, and neutrons, neutral particles, are found in the atom's nucleus (central core).
How it works
Electrons, negatively charged particles, orbit the nucleus in shells or energy levels at varying distances from the centre.
Why it matters
The number of protons determines an element's atomic number and identity, while the number of electrons typically equals protons in a neutral atom.
Key detail
Understanding atomic structure explains how atoms bond with each other and why different elements have different chemical properties.
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Quick notes
• Protons: positive charge, in nucleus.
• Neutrons: neutral charge, in nucleus.
• Electrons: negative charge, orbit nucleus.
• They orbit in shells/energy levels.
• Proton number = atomic number, element identity.
• Electron number = proton number (neutral atom).
• This explains atomic bonding.
• It explains different elements' properties.