1. The periodic table is arranged according to atomic number from smallest to largest. Hydrogen is the smallest atom/element on the periodic table.
2. The periodic table is also split into 3 categories: Metals, Metalloids, and Non-Metals. Each category has a unique set of properties. Please list them below.
3. The periodic table is also organized into groups/families (columns) and periods (rows).
4. There are 18 groups on the periodic table. Each group has a name. The most important for you to know are:
Group 1: Alkali Metals (not hydrogen)-solids, soft metals, very reactive, conduct electricity
Group 18: Noble Gases-gases, not reactive
5. Periods are rows. There are 7 periods on the periodic table.
6. Elements change gradually as you move across the periodic table. Both physical and chemical properties change. Examples of physical properties are state and hardness. The elements on the far left are metals and the ones to the far right are non-metals; the metals change from soft metals in Group 1 to harder metals in Group 3-12. One example of a chemical property is reactivity. Group 1 is the most reactive but Group 18 is the least reactive.
7. Elements in a group/family are more alike than elements in a period. Elements in a group/family share similar properties. For example, all elements in group 1 are very reactive solids and all elements in Group 18 are non-reactive gases. As you move down a group, the atomic size increases (the atom gets bigger).