Periodic Patterns

THE PERIODIC TABLE

Design of the Periodic Table Classification of Element

By looking at where a element is on the periodic table, you can tell about it’s chemical and physical properties

Columns (18) Up and down Called Families/Groups Elements in Families have similar properties

Rows (7) Side to Side Called Periods Elements in periods DO NOT have similar

properties

The first two and last six columns are numbered 1A-8A, relates to the # of electrons in their OUTER shell.

1

2

3

4 5

6

7

1A

2A 3A 4A 5A 6A 7A

8A

Properties of the metals These elements are metals:

Physical Properties Luster- Shininess Ductile and

malleable- able to be drawn into wires and hammered into sheets

Chemical Properties Corrosive- wearing

down due to chemical reaction

Easily lose electrons

Alkali Metals Group 1 Very reactive Form +1 ions Cations Examples: H, Li,

Na

Alkaline Earth Metals

Group 2 Reactive Form 2+ ions Cations Examples: Be, Mg, Ca, etc

Transition Metals

Groups 3B-12B on the Periodic Table Much less reactive than Alkali or

Alkaline Earth Metals Only 1 that is a liquid at room temp

Mercury – Hg Examples: Cr, Co, Ni, Fe, Cu, Ag, Au

Properties of non-metals These elements are non-metals:

Physical Properties No Luster Not ductile or

malleable Chemical

Properties Tend to gain

electrons

Nonmetals

Not good conductors Found on right side of periodic table

– AND hydrogen Usually brittle solids or gases

Halogens

Group 17 Very reactive Form 1- ions Anions Examples: F, Cl, Br, etc

Properties of Noble Gases These Elements are Noble gases:

Group 18 Unreactive, inert,

“noble” Have a 0 charge, no

ions Examples: He, Ne,

Ar, Kr, etc

Properties of Metalloids

These Elements are metalloids

Form the “stairstep” between metals and nonmetals

Properties Can have both of

metals and non metals

Sometimes called semiconductors

Example: Can be shiny or

dull, malleable or not…

Properties of rare Earth metals These Elements are rare Earth metals:

Properties: The rare earths are

silver, silvery-white, or gray metals.

The metals have a high luster, but tarnish readily in air.

The metals have high electrical conductivity.

1

2

3

4

5

6

7

Lanthanides - part of period 6

Actinides - part of period 7

Atoms Elements are made of

particles called atoms Atoms are the smallest

pieces of matter that contain all the properties of a specific element

Each element contains only one type of atom

Inside the Atom Atoms are made up of

smaller particles These particles are found

in different regions of the atom

Protons Positively charged particles found in nucleus of

atom Have an electrical charge of +1 Mass of 1 a.m.u.

Neutron Neutral particles found in nucleus of atom Have no electrical charge Mass of 1 a.m.u.

Electron Negatively charged particles found in electron

cloud Have an electrical charge of -1 Constantly moving around outside nucleus Have essentially no mass

Structure of the Periodic Table

Atomic number – Tells us how many protons and electrons are in an atom The number of protons defines the

identity of the atom Atomic Mass – gives the mass of a

single atom in atomic mass units (amu) Atomic mass = # p+ + n0

Oxidation Number – tells us what the atom wants to do with electrons

Structure of the Periodic Table The Periodic Table also tells us about the electron structure of an atom Each Period represents an

energy level in the electron cloud Ex: Na is in the 3rd Period, therefore

its electron cloud will consist of 3 Energy levels

The Group number represents the number of electrons in the outer energy level Ex: Na is in a Group 1 element,

therefore it has one electron in the outer energy level

The number of boxes in each period indicate the number of electrons that the energy level can hold

Comprehension Check

How many energy levels does aluminum’s electron cloud have? 3

How many electrons are in aluminum’s 2nd energy level? 8

How many electrons are in aluminum’s 3rd energy level? 3

Symbols Elements are listed by their chemical

symbols Symbols are usually either one

capital letter like C for Carbon, or one capital and one lowercase letter like Ne for Neon

Periodic Table

The periodic table gives much information we need to learn more about the atom of each element

Atomic Mass

The average atomic mass is the number at the bottom of this square

Found by averaging the natural abundances of its isotopes

Mass # = # p+ + # n0

Atom Math

Atomic NumberSymbol

Element Name

Atomic Mass

Atom Math

Protons Electrons

Protons Neutrons

Practice

30815.9998

88

Zn

Oxygen

65.393035

30

Lithium

36.941

3

43

# n0 = Mass # - Atomic #

Isotopes

Atoms of the same element with different mass numbers.

C126

Mass #

Atomic #

Nuclear symbol:

Hyphen notation: carbon-12

Isotopes

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How many eggs go in an egg carton?

The Role of Electrons in Bonding The sharing or transfer of electrons is what holds atoms together in a compound Typically, only the electrons in the outer

energy level are used for bonding. These electrons are called Valence Electrons The outer energy level is called the Valence

Shell

Octet Rule: atoms want to have a full valence shell (8 valence electrons)

Atoms react with one another in an attempt to gain or lose electrons to fill their valence shell

During a reaction, electrons can be shared or completely transferred

Comprehension Check

How many valence electrons does phosphorus have? 5

How many electrons does phosphorus have to gain or lose in order to fill its valence shell? Lose 5, Gain 3

Comprehension Check- To Gain or Not to Gain nitrogen beryllium xenon carbon

Gain 3 Lose 2 None Gain/Lose 4

oxygen lithium chlorine boron

Gain 2 Lose 1 Gain 1 Lose 3

Types of Bonds Ionic Bonds – Results from the complete

transfer of electrons Results in a formation of two charged atoms

called ions The atom that gains electrons becomes negatively

charged and is called an anion The atom that loses electrons becomes positively

charged and is called a cation The attraction of the positive and negative

charges results in a very weak bond

Covalent Bonds – Results from the sharing of electrons

The shared electrons create a very strong bond These are the bonds that make molecules possible

Oxidation Numbers

Oxidation Numbers tell us how many electrons an atom is willing to lose or gain Positive oxidation numbers indicate that

the atom can lose that many electrons Negative oxidation numbers indicate

that the atom can gain that many electrons

Some atoms have more than one possibility