The periodic table arranges all the chemical elements in a specific way. Patterns are visible in the way that elements behave, and this allows us to make predictions about other elements.

In discussing halogen reactivity (as covered in Core Idea), it is a common practice to argue that as you go down the Group 17 elements it becomes harder for the elements to gain an electron to form a ...

sulfur and oxygen share similarities in chemical reactivity. However, sulfur's position lower in the periodic table endows its compounds with distinct properties that are advantageous to ...