Anatomy of the Atom

Alkali metals Think back to Friday … Watch this!

Learning Goals We are learning to identify parts of the atom. We are learning to draw Bohr-Rutherford diagrams.

in energy levels surrounding nucleus Subatomic Particles In each atom, there are three subatomic particles: Name Symbol Relative Mass Electric Charge Location Proton p 1836 1+ nucleus Neutron n 1837 Electron e 1 1- in energy levels surrounding nucleus

Anatomy of an Atom Shells p n Nucleus (proton and neutron) Electron

Ahhhhhh, I c… element name atomic number element symbol atomic mass

Atomic Number identifies every element on PT equals the amount of protons in an atom no two elements have the same atomic number.

Atomic Number also tells us the number of electrons present in all neutral atoms: # of protons = # of electrons.

What if!? +

Cha-ching

Atomic mass the mass of an atom in atomic mass units

Mass number the number of protons and neutrons in an atom’s nucleus. equals the atomic mass, rounded

Finding Nemo … or Neutrons To determine the number of neutrons in an element … math is needed! # neutrons = (mass number) – (atomic number)

Whoa, what!? Isotope – same elements with different numbers of neutrons thus have a different mass C-12 and C-14 (number indicate the mass)

Al Aluminum 27 13 Write aluminum in standard notation. How many protons? How many electrons? How many neutrons? Al 27 13

Bohr-Rutherford Diagrams Draw the nucleus as a solid circle. Put the number of protons (atomic number) in the nucleus with the number of neutrons (mass number – atomic number) under it. Place the number of electrons (same as protons) in orbits around the nucleus by drawing circles around the nucleus. Remember: 1st shell – 2 electrons 2nd shell – 8 electrons 3rd shell – 8 electrons

Example Phosphorous!

Just how small are atoms? Watch!!

Learning Goals We are learning to identify parts of the atom. We are learning to draw Bohr-Rutherford diagrams.

Please Complete … Bohr diagram sheet Textbook 6.7 #1-3,5