Structure of The Atom Not the Adam

Basic Structure of the Atom A positively charge proton A neutrally charged neutron The negatively charged electron travels around the nucleus

Relative Masses of the Sub-atomic Particles Proton has a mass of 1.0073 amu or 1 amu Neutron has a mass of 1.0087 amu or 1amu Electron has a mass of 5.49 x 10-4 amu One amu equals 1.66 x 10-27kg Atomic Mass Unit (amu) is a unit of mass equal to one-twelfth (1/12) of the mass of a carbon 12 atom.

The Relative Masses of the Particles

What is in the nucleus? The nucleus contains the Protons – positively charged Neutrons – neutral charged The nucleus has a positive charge

Relative Size of Nucleus

Atomic Number The atomic number represents the number of protons in an element Each element has its own Atomic Number The number of protons is what determines what type of atom. The number of protons equals the number of electrons in an atom

Atomic Symbol Elements are represented by a symbol The symbol is either one upper case letter or an upper case and a lower case O C Na Mg Si Cl NEVER MG or NA or SI or CI

On periodic table Top number Symbol Atomic mass Atomic number The bottom number

Atomic Mass The atomic mass gives the mass of the protons and neutrons in an atom The atomic mass less the atomic number gives the number of neutrons # of Neutrons = Atomic mass-Atomic Number

Determine the Number of Neutrons in Ca H Bi Mo O 20 neutrons 0 neutrons 126 neutrons 54 neutrons 8 neutrons

Atomic Weight Elements exist in different forms or isotopes in nature Every atom of an element has the same number of protons and electrons but different number of neutrons The atomic weight of an element listed on the periodic is the weighted average of all the naturally occurring isotopes