Chapter 1- Chemical BondingSection 1: pages 4-7

Electrons and Chemical Bonding

How many words can you make from the word science?

CEE

CEES

CENSE

CINE

CINES

EN

ENS

ES

ICE

ICES

IN

INS

IS

NEE

NICE

NIECE

NIECES

SCENE

SCENIC

SCIENCE

SEC

SEE

SEEN

SEI

SEINE

SEN

SI

SIC

SICE

SIN

SINCE

SINE

Bellringer

• Identify the elements in these compounds.• Are these compounds similar to each other?

C6H12O6 C2H5OH

C6H8O6 C6H8O7

The atoms of just three elements (C,H,O) combine to form sugar, alcohol, and citric acid.

VOCABULARYChemical Bonding – the joining of atoms to form new substances.

Chemical Bond – a force of attraction that holds two atoms together.

Valence Electrons – the electrons in the outermost energy level of an atom. These are the electrons involved in forming chemical bonds.

Electron Number and Organization

Electrons are tiny, very light particles that have a negative electrical charge (-).

Protons are much larger and heavier than electrons and have a positive charge

Neutrons are large and heavy like protons, however neutrons have no electrical charge.

Electron Number and Organization

Atomic Number tells you the number of protons and electrons in the atom.

Valence Electrons and Bonding

Valence Electrons are the electrons in the outermost shell. It is these electrons that form bonds.

The number of some Valence Electrons is determined by its periodic table group.

Families on the Periodic Table• Elements on the periodic table can be grouped

into families bases on their chemical properties.

• Each family has a specific name to differentiate it from the other families in the periodic table.

• Elements in each family react differently with other elements.

Each row is called a “period”

1st Period = 1 Shell

2nd Period = 2 Shells

3rd Period = 3 Shells

4th Period = 4 Shells

The elements in each period have the same number of shells

www.chem4kids.com

Groups

Each column is called a “group”Each element in a group has the same number of electrons in their outer orbital, also known as “shells”.

Group 1 = 1 electronGroup 2 = 2 electrons

Group 8 = 8 electrons

Except for He, it has 2 electrons

The electrons in the outer shell are called “valence electrons”www.chem4kids.com

3, 4, 5, 6, 7