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?