Atomic Structure and the Periodic Table
Everything around you is made of atoms - the tiny building blocks of matter that you can't see but are absolutely everywhere. Understanding atoms is like having a secret code to unlock how chemistry works!
Elements are pure substances made of only one type of atom, whilst compounds contain two or more different elements chemically bonded together. You'll need to master writing chemical formulae and balanced symbol equations to show what happens in reactions. For Higher Tier students, half equations and ionic equations are also essential.
The atomic model has evolved massively over time thanks to scientists like James Chadwick. We've moved from the old "plum pudding" model to today's nuclear model, where protons and neutrons sit in the nucleus whilst electrons orbit around it. Remember: protons are positive, electrons are negative, and neutrons are neutral.
Isotopes are atoms of the same element with different numbers of neutrons, which affects the relative atomic mass. The periodic table arranges elements by atomic number, and elements in the same group have similar properties because they have the same number of outer electrons. Groups like the alkali metals (Group 1), halogens (Group 7), and noble gases (Group 0) each have distinctive characteristics you'll need to recognise.
Key Tip: Use the periodic table as your chemistry roadmap - it tells you everything about an element's behaviour and properties!
