All practice pages/Interatomic theory
Alkali metals, halogens, noble gases and the rest: where each family sits, how it behaves, and a quiz to make it stick.
Elements in the same column have the same number of valence electrons, so they behave alike. That is why the table is read in families. Tap any cell for its name and family, or tap a family in the key to light up its members.
Tap an element.
Select every one that fits, then Check. If none of them fit, Check with nothing selected.