CHEMISTRY PART 1
Atoms and The Periodic Table
Definitions

Chemistry:
 The
study of the structure and properties of
matter.

Element:
A
substance with only one single type of atoms.
 Found on the Periodic Table (page 420).
Definitions

Atom:
 The

smallest part of an element.
Molecule:
A
group of atoms bonded together.
Parts of an Atom

Protons:
 Positive
charge (+1)
 In the nucleus (centre)

Neutrons:
 No
charge (0)
 In the nucleus

Electrons:
 Negative
charge (-1)
 In clouds (shells) that surround the nucleus
Parts of an Atom

Basic Atomic Structure
Atoms

Atomic Number (Z):
 The
number of protons.
 Gives the atom its place on the Periodic Table.
Atoms

Atomic Mass (A):
 The
nucleus has the most mass.
 Often rounded so:
 number
of protons + number of neutrons
 number of neutrons = atomic mass – number of protons
Atoms

Number of Electrons:
 When
the atom is neutral:
electrons is same as protons
Periodic Table

Contains elements and gives information
about them.
 Element’s
symbol
 Name of Element
 Atomic Number
 Atomic Mass
Periodic Table Example

Element’s symbol


Name of Element


8 (8 protons)
Atomic Mass


Oxygen
Atomic Number


O
15.999 (16 – 8 = 8 neutrons)
Number of electrons

8
Periodic Table Activity

Use your periodic table to find:
Element Name
 Number of Protons
 Number of Electrons
 Number of Neutrons






C
Be
H
N
Ne
Periodic Table Activity

C
 Carbon
6
6
 12
–6=6
Periodic Table Activity

Be
 Beryllium
4
4
9
–4=5
Periodic Table Activity

H
 Hydrogen
1
1
1
–1=0
Periodic Table Activity

N
 Nitrogen
7
7
 14
–7=7
Periodic Table Activity

Ne
 Neon
 10
 10
 20
– 10 = 10
Practice


Worksheet.
Page 97 # 11 – 14 and 21.