Across a period from left to right, the covalent radius decreases. As you move from left to right across the periodic table, atoms have more electrons in their outer energy level and more protons ...

The ions formed have a full outer electron shell, so are very stable. See the study guide on groups in the periodic table for more information.

mind mapping and mnemonics can help in memorising the periodic table and other important topics. “If these charts are added in a revision corner of the room which is at least glanced upon once ...