What you'll learn
Using the periodic table to predict reactions.
Groups and trends
- Group 1 (alkali metals), Group 7 (halogens) and Group 0 (noble gases).
- Reactivity trends down groups; displacement reactions.
Tests
- Gas tests: hydrogen (squeaky pop), oxygen (relights splint), carbon dioxide (limewater milky), chlorine (bleaches litmus).
Exam tips
- Link position in a group to reactivity.
- Learn each gas test and its positive result.
Common mistakes
- Reversing the reactivity trend for halogens vs alkali metals.
- Confusing the gas tests.