Atomic Number Atomic Mass Subatomic Particles Atomic Number Atomic Mass

Parts of the Atom Protons Neutrons Electrons Positive charged particles found in nucleus Neutrons Neutrally charged particles found in the nucleus Electrons Negatively charged particles found outside nucleus

Atomic Number The atomic number of an element is the number of protons in the nucleus. The atomic number of an atom will never change. If the number of protons in an atom changes, the atom no longer has the properties of that atom

Atomic Mass The mass number is the total number of protons and neutrons in the nucleus. That means that the mass number is the total number of protons plus the total number of neutrons.

Particles in an Atom Using the atomic mass and atomic number the individual number of electrons, protons and neutrons can be calculated mass number – atomic number = number of neutrons (#Protons & #Neutrons) - (# protons) = # neutrons

Isotopes An element having the same number of protons but different numbers of neutrons. All atoms of an element have the same atomic number and therefore the same number of protons Atoms of the same element but different numbers of neutrons are called Isotopes

Valence Electrons link Valence Electrons are the outer most electrons that compose an atom They determine bonding properties of the atom Protons and Neutrons in the nucleus Electrons in the electron cloud per orbital or levels 2 in the first level 8 in the second level 18 in 3rd level 32 in 4th level

Assignment Atom Drawings worksheet