The Periodic Table

What is an element?

All matter is made up of atoms, and each unique atom represents a different element. Atom – The smallest unit of matter that can

take part in a chemical change and keep its characteristics.

A pure substance that cannot be broken down into simpler substances. Elements are made up of identical atoms.

Subatomic Particles

Subatomic Particle A particle smaller than an atom.

Electrons, Neutrons and Protons

Today’s Atom – The Periodic Table

Chemical symbol An abbreviation of the name of an element.

E.g. Carbon = CHelium = He

There are 2 rules for finding the symbol for an element: A single-letter symbol is always capitalized

E.g. Oxygen = O The first letter of a two-letter symbol is always

capitalized. E.g. Lithium = Li

The Periodic Table

Period: the horizontal rows of the periodic table. Numbered 1-7 Indicates the number of electron shells or

orbitals.Group/Family:

The vertical columns of the periodic table. Contain elements with similar properties They all have the same number of outer shell

electrons called : VALENCE ELECTRONS

Alkal

i

Met

als

Hydrogen is an exception. It is an explosive gas but is placed in the Alkali metals because it only has 1

electron.

Alkal

ine

Earth

Met

als

Transitional Metals

Staircase

= M

etalloids

Chalcogen

s Halogens

Noble

Gases

Metals: To the left of the staircase

Non-Metals: To the right of the staircase

The Main families/Groups

Group IA: Alkali MetalsGroup IIA: Alkaline Earth MetalsGroup VIA: ChalcogensGroup VIIA: HalogensGroup VIIIA: Noble GasesNote: Hydrogen is a family all to itself.http://www.dayah.com/periodic/

The Periodic Table

There are 3 main types of elements on the periodic table: Metals Non-metals Metalloids

 

Metals

Most common form of matter75% of the P.T. are metalsOn the left side of the “staircase”Lustre (shiny)Silver/Gold colourMalleable (flexible, bendable, flattened)Ductile (drawn into wires)Solid (Hg is liquid, H is a gas)Conducts heat and electricity

Non-Metals

Located on the right side of the periodic table15% of elements are non-metalsOpposite of metalsNo lustreBrittle (breaks)Does not conduct heat or electricity wellInsulatorsSolids, some gas, liquids

Metalloids

Surrounds the stair case6-10% of elements on the P.T.Some properties of metals but not all.Solid at room temp.Some have lustreSemi-Conductors

Hindenburg

May 6, 1937, the Hindenburg carrying 61 crew and 36 passengers took flight.

This 804-foot dirigible filled with over 7 million cubic feet of hydrogen was a crowning achievement of its age. Never before or since has a larger aircraft taken flight.

Many theories were talked about and investigated: sabotage, mechanical failure, hydrogen explosions, lightning or even the possibility that it was shot from the sky.

http://www.youtube.com/watch?v=xiAT9xvTVKIhttp://www.youtube.com/watch?v=F54rqDh2mWA

The Elements

Element kitHow small is an atom?

http://www.youtube.com/watch?v=xqNSQ3OQMGIAlkali metals in water!

http://www.youtube.com/watch?gl=CA&hl=en&v=Ft4E1eCUItI

http://www.youtube.com/watch?v=m55kgyApYrY&feature=related

How to read the periodic table

Jersey analogy

Noble Gases = Team Name Atomic # 36 = Player # Symbol Kr = Mascot Krypton = Player Name Mass 83.80 = Stats

Noble Gases

Bohr Diagrams

Protons and Neutrons are found within the nucleus.

Electrons travel around the nucleus in specific paths called orbits or shells. These shells exist whether they are occupied or not.

The 2-8-8 Rule

1st shell – holds a max of 2 electrons2nd shell – holds a max of 8 electrons3rd shell – holds a max of 8 electrons

How do you find the number of Protons and Electrons?

Each element has a unique atomic number that identifies how many protons are in one atom of that element. The Atomic number = the number of protons

Atoms must have equal numbers of protons and electrons. Therefore: The Atomic number also = the number of

electrons• E.g. Calcium has 20 protons AND 20 electrons

“P.E.A rule” = # of protons = # of electrons = atomic number

How do you find the number of Neutrons?

You simply take the "Atomic Mass" (the larger number), round the atomic mass to a whole number to get the Mass Number, and subtract the Atomic Number from it. # Neutrons = Mass Number - Atomic Number

Example: Hydrogen (H) atomic number = 1 number of protons = 1, and number of electrons = 1 atomic mass = 1.008 which rounds to 1 #of neutrons = atomic mass – atomic number = 1-1

= 0

Summary Table

Subatomic Particle

Symbol and Charge

Mass Location

Proton p+ 1 amu Nucleus

Neutron n 1 amu Nucleus

Electron e- 1/1837 amu Electron shells

Note: AMU = Atomic Mass Unit

Atomic Symbols

Note that the mass number may be on the top or bottom (the mass number is always the larger of the two)

# of protons in the atom

# of Electrons in the atom

# of neutrons in the atom

Atomic mass of the atom

Atomic # ofthe atom

Elementname

Chemicalsymbol

7 7 7 14.007 7 Nitrogen N

5 5 6 10.811 5 Boron B

1 1 0 1.0079 1 Hydrogen H

20 20 20 40.08 20 Calcium Ca

30 30 35 65.39 30 Zinc Zn

13 13 14 27 13 Aluminum Al

9 9 10 19 9 Fluorine F

23 23 28 51 23 Vanadium V

17 17 18 35 17 Chlorine Cl

3 3 4 6.941 3 Lithium Li

79 79 118 196.97 79 Gold Au

11 11 12 23 11 Sodium Na

33 33 42 74.922 33 Arsenic As

50 50 69 118.71 50 Tin Sn

19 19 20 39.098 19 Potassium K

Elemental Symbols

Most elemental symbols are based off the name of the element.

Some derive their name from other sources: Gold = Au (Latin name aurum) Silver = Ag (Latin name argentum) Lead = Pb (Latin name plumbum) Tungsten = W (from the German Wolfram)