Notes

The 3 major classifications:
METALS- characterized by their hardness, luster, malleability, and the ability to conduct heat and electricity. metallic elements are solid at room temperature(except mercury)
NON-METALS- non-metallic are those elements that doesn't posses metallic luster, and are poor conductors of both heat and electricity. most of them are gases and solids at room temperature
(except bromine which is liquid at room temperature)
METTALOIDS- it possesses characteristics of metals(can conduct electricity) and properties of non-metals(brittle and soft). for example: silicon, a brittle solid that can conduct electricity

The s, p, d, f blocks
the periodic table is also divided into four blocks. these blocks are based on the electon configuration of an element

Elements are organized on the table according to their atomic number , usually found near the top of the square. The atomic number refers to how many protons an atom of that element has. For instance, hydrogen has 1 proton, so it’s atomic number is 1

Different periodic tables can include various bits of information, but usually contains: atomic number, symbol, atomic mass,. number of valence electrons, and state of matter at room temperature.

Atomic Number-This refers to how many protons an atom of that element has . No two elements, have the same number of protons. Bohr Model of Hydrogen Atom Wave Model

Atomic Mass-Atomic Mass refers to the “weight” of the atom. It is derived at by adding the number of protons with the number of neutrons .H This is a helium atom. Its atomic mass is 4 (protons plus neutrons). What is its atomic number?

Symbols-All elements have their own unique symbol. It can consist of a single capital letter , or a capital letter and one or two lower case letters .C Carbon Cu Copper Au Gold

Valence Electrons-The number of valence electrons an atom has may also appear in a square. Valence electrons are the electrons in the outer energy level of an atom. These are the electrons that are transferred or shared when atoms bond together.