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.