Practice and Revision - Atomic Structure
Let us practise and revise what we learned about atomic structure. Atoms consist of a nucleus (with protons and neutrons) surrounded by elec
Core concept
Protons (positive charge) and neutrons (no charge) are found in the nucleus, while electrons (negative charge) orbit around it in shells.
How it works
The atomic number equals the number of protons, uniquely identifying each element, while the mass number is protons plus neutrons.
Why it matters
Electrons are arranged in shells around the nucleus, with the outermost shell (valence electrons) determining how an atom bonds with others.
Key detail
Understanding atomic structure helps explain the periodic table's organisation and predict how elements will react chemically.
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Quick notes
• Protons and neutrons are in the nucleus.
• Protons are positive; neutrons have no charge.
• Electrons are negative, orbiting in shells.
• Atomic number = number of protons.
• Mass number = protons + neutrons.
• Valence electrons are in the outermost shell.
• They determine bonding behaviour.
• Atomic structure explains the periodic table's organisation.