Lesson 3 Patterns and The 

Periodic Table PART 1

Textbook p. 184-187

Organizing the Elements

The element can be classified as:1.________________ (left-side)2.________________(right-side)3.________________ (step-like line that divides metals from non-metals)

MetalsNon-metalsMetalloids

Metals, Non‐Metals, Metalloids

Chemical Groups (Families)Chemical Group / Families: arrange in columns

Periods

Periods

Periods: arranged in horizontal row

Group 1 elements (except hydrogen):

_____________________

Group 2 elements:_______________________

Group 17

elements:______________________

Group 18 elements:_____________________

Chemical Groups (Families)

alkali metals

alkaline earth metals

halogens

noble gases

Chemical Groups (Families)

alkaline earth metals

alkali metals noble gases

halogens

Find the number of protons, electrons, and neutrons from the periodic table:

Number of protons = Atomic number Number of electrons = Number of protons

= Atomic number Number of neutrons = Mass number –

Atomic number

(Mass number = Number of neutrons + number of protons)

Find the number of protons, electrons, and neutrons from the periodic table:

What is Atomic Number?

Number of ______________ in the element

Used to identify the element.

protons

What is Mass Number?

= Number of _________

+ number of ______= _______ the atomic mass to the nearest whole number

protons neutronsRound

What is Atomic Mass?

__________________ of an element in the environment

E.g. Naturally occurring magnesium:

(79 %)

(10 %) (11 %)

(79% x 23.99) + (10% x 24.99) + (11% x 25.98) = 24.31

Average mass

1224Mg

1225Mg 12

26Mg

Atomic Number & Atomic Mass

Atomic Mass

Atomic Number = number of protons

= average mass of an element in the environment

Atomic Mass & Mass Number 

Atomic Mass= 6.94 Round to nearest whole number

Mass Number = 7

Element Name & Symbol

Element Name

Element Symbol

Element Symbol

Element Symbol

Standard Atomic Notation

Mass Number

Atomic Number

Element Symbol

Fill in the Chart.Element Name Atomic

Number Mass

Number Standard

Atomic Notation

Number of

Protons

Number of

Electrons

Number of Neutrons

Copper 29 64

Phosphorus

3 4lithium

15

3

31

7

2929 64 – 29= 35

15 1531 – 15= 16

3

What is an isotope?Atoms of the ___________ element

that

have different number of _____________(i.e. same atomic number but different mass number

sameneutrons

lithium-6 lithium-7 lithium-8

Fill in the Chart….Element Name Atomic

Number Mass

Number Standard

Atomic Notation

Number of

Protons

Number of

Electrons

Number of Neutrons

Copper-63 29 63

Copper-65 29 65

2929 63 – 29= 34

29 2965 – 29= 36

Same atomic number

Different mass number

Different # of neutrons