This topic summary covers Knowledge Organiser: The Periodic Table within The Periodic Table for GCSE Chemistry. Revise The Periodic Table in Atomic Structure for GCSE Chemistry with 22 exam-style questions and 24 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 13 of 13 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Knowledge Organiser: The Periodic Table
Key Terms
- Group: Vertical column, same outer electrons
- Period: Horizontal row, same number of shells
- Metal: Left/centre, conducts, forms + ions
- Non-metal: Right, poor conductor
- Atomic number: Basis for ordering
Must-Know Facts
- Group = number of outer shell electrons
- Period = number of occupied shells
- Same group = same outer electrons = similar properties
- Group 1: reactivity increases down
- Group 7: reactivity decreases down
- Group 0: full outer shell, unreactive
- Ordered by atomic number, NOT atomic mass
Key Equations
- Group number = number of outer shell electrons
- Period number = number of occupied electron shells
- Atomic number = proton number (ordering principle)
Common Mistakes
- Saying the table is ordered by atomic mass: Mendeleev used mass, but the modern table is ordered by atomic number (proton number)
- Confusing group and period trends: Group 1 reactivity increases DOWN; Group 7 reactivity decreases DOWN
- Saying metals are only on the left: Transition metals occupy the large central block too
- Forgetting Group 0 is unreactive: Full outer shell = stable = won't form ions or bonds under normal conditions
Practice questions for The Periodic Table
How are elements arranged in the modern periodic table?
Mendeleev's periodic table was eventually accepted by other scientists. Explain why scientists were convinced that his table was correct.
Quick recall flashcards
Where are non-metals found?
On the right side of the periodic table
What are the Group 1 elements called?
Alkali metals (Li, Na, K, Rb, Cs, Fr)