Post on 26-Dec-2015
Atoms and Atomic Structure
Protons, Neutrons, ElectronsAtomic/Bohr Models
The Atom3 parts
1. Protons = positive charge
2. Neutrons = neutral charge
3. Electrons = negative charge
Protons +
Neutrons
=Nucleus
ElementsA pure substance that cannot be broken
down into other substances
Water
Hydrogen Oxygen
Gold
Gold
Protons, Neutrons, ElectronsAll atoms we draw will have equal protons
and electrons
1
H1.0
Atomic Number
Atomic Symbol
Atomic Mass
Protons, Neutrons, Electrons# of protons = look at the atomic number
# of electrons = look at the atomic number
# of neutrons = subtract the atomic number from the atomic mass
1
H
1.0
Atomic NumberAtomic SymbolAtomic Mass
Practice2
He
4.0
11
H
23.0
21
Sc
45.0
19
K
39.0
P = N = E =
P = N = E =
P = N = E = P = N = E =
Periodic Table Parts
Periods: move from left to right across the periodic table (7 periods)
Groups: move from top to bottom down the periodic table (18 groups)
The Periodic Table
Group 1Alkali Metals
Lithium
Sodium
Potassium
Rubidium
Cesium
Francium
Metals
Very Reactive
1 Electron in outer level
Group 2Alkaline-Earth Metals
Beryllium
Magnesium
Calcium
Strontium
Barium
Radium
Metals
Reactive, but not as reactive as Alkali Metals
2 Electrons in outer level
Groups 3-12Transition Metals
1 or 2 Electrons in outer level
Lanthanides and Actinides
Groups 13-16 w/ MetalloidsBoron Group 13
Reactive
Solid at Room Temperature
3 Electrons in outer level
Groups 13-16 w/ MetalloidsCarbon Group 14
Reactivity varies among the elements
Solid at room temperature
4 Electrons in outer level
Groups 13-16 w/ MetalloidsNitrogen Group 15
Reactivity varies among elements
All but nitrogen are solid at room temp
5 Electrons in outer level
Group 13-16 w/ MetalloidsOxygen Group 16
Reactive
All but oxygen are solid at room temp
6 Electrons in outer level
Group 17Halogens
Very Reactive
React violently with alkali metals to form salts
7 Electrons in outer level
Group 18Noble Gases
Unreactive
Colorless, odorless gases at room temp
8 Electrons in outer level (2 for Helium)
What About Hydrogen?Hydrogen stands alone
Reactive
Colorless, odorless gas at room temp
Explosive reaction with oxygen
Groups are arranged due to all members top to bottom having similar Physical and Chemical properties.