1. The horizontal rows of the periodic table are called PERIODS.

2. The elements in any group of the periodic table have similar physical and chemical properties!
The vertical columns of the periodic table are called GROUPS, or FAMILIES.

3. Periodic Law
When elements are arranged in order of increasing atomic number, there is a periodic pattern in their physical and chemical properties.

4. Alkali Metals

5. Alkaline Earth Metals

6. Transition Metals

7. InnerTransition Metals
These elements are also called the rare-earth elements.
InnerTransition Metals

8. Halogens

9. Noble Gases

10. The s and p block elements are called REPRESENTATIVE ELEMENTS.

11. The periodic table is the most important tool in the chemist’s toolbox!

12. You must know the following periodic trends and the reasons behind them:
Atomic size (radius),
Ionic size (radius),
Ionization energy,
Electronegativity
m.p. and b.p.