Slide 1

Atomic Structure

Slide 2

The Atom Smallest form of an element that still retains that elements properties Basic building block of matter Made of: Protons Neutrons Electrons

Slide 3

The Atom Composed of: Nucleus Electron Cloud

Slide 4

The Nucleus Positively charged Protons and neutrons Protons positively charged Neutrons neutrally charged Neutrons act like glue

Slide 5

The Electrons Negatively charged Occupy the Electron cloud surrounding the nucleus Arranged into shells or orbitals Electrons are NOT moving in perfect orbits around the nucleus. The electron movement is unpredictable Cloud gives us approximate location of where electrons are

Slide 6

Slide 7

Subatomic Particles LocationChargeMassSpecial Fact ProtonsNucleusPositive (+)1 amuNumber of protons determines the identity of the element NeutronsNucleusNeutral1 amu ElectronsElectron CloudNegative (-)0.00054 amuElectron cloud takes up 99.9999999% of the volume of the atom

Slide 8

Properties of Atoms Atomic Number Mass Number Average Atomic Mass

Slide 9

INSIDE THE SQUARES

Slide 10

Atomic Number Number of protons in the nucleus of an atom Each element has its own specific atomic number In a NEUTRAL ATOM, this is also the number of electrons

Slide 11

(Average) Atomic Mass An average mass of each of the different isotopes found for that element in nature For example, Chlorine has 2 different isotopes Each one has 17 carbons and a different number of neutrons (This is what an isotope is. More on that later) If you take the average atomic mass of every single carbon atom that exists, the average mass will be 35.453 amu

Slide 12

Mass Number Mass number is the mass of a SPECIFIC isotope of an atom. It is the SUM of the protons and neutrons in the nucleus Mass Number = (# of neutrons) + (# of protons) Mass Number = Atomic Mass It is not the average unless we say AVERAGE How do we find # of neutrons?

Slide 13

So how do I know what the Mass Number is? I will tell you. One of two ways: 1) Give you the mass number or the neutrons in a table. If I dont give it to you, get the rounded # off the PT 2) Tell you in the symbol. A) Isotope Notation: B) Isotope Name: Sodium-23

Slide 14

Figuring out some element parts ElementSymbolAtomic #ProtonsNeutronsMass # Boron-11B Carbon -1266 Magnesium-231223 Copper-642935 20

Slide 15

Figuring out some element parts ElementSymbolAtomic #ProtonsNeutronsMass # Boron-11B55611 Carbon -12C66612 Magnesium-23Mg12 1123 Copper-64Cu29 3564 ????20?