# Chapter 5 The Periodic Table.

## Presentation on theme: "Chapter 5 The Periodic Table."— Presentation transcript:

Chapter 5 The Periodic Table

Dimitri Mendeleev

Arranged the elements into rows in order of increasing mass.
Mendeleev’s Proposal Arranged the elements into rows in order of increasing mass. Elements with similar properties were in the same column.

Mendeleev ‘s Predictions
Mendeleev predicted where new elements would appear in the table. Properties of new elements showed how useful his periodic table could be.

Homework 5-1 Worksheet Due: 11/5/08

Arrangement of the elements:
Periodic Table Arrangement of the elements: Chemical Properties Atomic Number Number of Protons

Group Vertical Column Repeating Chemical Properties Increase Mass

Group 11-1B

(Number of Electrons in the Outer Energy Level!!)
Groups Same number of Valence Electrons (Number of Electrons in the Outer Energy Level!!)

Be Mg Ca Group 2 Sr Ba Ra

Periods Horizontal Rows Same Number of Energy Levels

Period - 2 Li Be B C N O F Ne

Names and Chemical Symbols
H - Hydrogen C - Carbon O - Oxygen Fe - Iron (ferrum) He - Helium Cu - Copper (cuprum) Hg - Mercury (hydragyrum) Co - Cobalt Unp - Unnilpentium Names and Chemical Symbols

Same group - Same number of electrons in their outer shells.
Group 1 (H) – 1e- Group 2 (Be) – 2e- Group 13 (B) – 3e- Group 14 (C) – 4e- Group 15 (N) – 5e- Group 16 (O) – 6e- Group 17 (F) – 7e- Group 18 (He) – 8e-

Atomic Number (# of Protons)
15 Phosphorus P Symbol Average Atomic Mass (31) Name

Atomic Mass Unit Atomic mass unit is equal to one-twelfth of the mass of the nucleus of a carbon-12 atom.

Atomic Mass Unit

p+ n0 Proton: Atomic Mass – 1amu Neutron: Atomic Mass – 1amu
Atomic Mass Unit p+ Proton: Atomic Mass – 1amu n0 Neutron: Atomic Mass – 1amu

Atomic Mass of 7 amu

Atoms of the same element can have different
Isotopes Atoms of the same element can have different numbers of neutrons.

Weighted Average The relative atomic mass (also known as atomic weight and average atomic mass) is the average of the atomic masses of all the chemical element's isotopes as found in a particular environment, weighted by isotopic abundance.

76% 24% Cl Cl 17 17 Proton 18 Neutrons 35 17 17 Proton 20 Neutrons 37
Isotopes of Chlorine Cl 17 35 17 Proton 18 Neutrons 76% Cl 17 37 17 Proton 20 Neutrons 24%

Average Weighted Mass of Chlorine
35.453amu

Non- Metals Metals Metalloids

Metals 75% of the Elements!!!

Physical Properties of Metals: Metallic shine or luster.
Usually solids at room temperature.

(Hammered, pounded, or pressed into different shapes
Metals 3. Malleable (Hammered, pounded, or pressed into different shapes without breaking.)

(Drawn into thin sheets or
Metals 4. Ductile: (Drawn into thin sheets or wires without breaking.) 5. Good conductors of heat and electricity.

Metals Metals tend to give up e-. Na

Francium Most Active Metal
Most Reactive Metals Fr Li Francium Most Active Metal

They have four major physical properties.
Non-Metals There are 17 nonmetals. They have four major physical properties.

Non-Metals Physical Properties 1. Rarely have metallic luster. 2. Usually gases at room temperature.

3. Nonmetallic solids are neither malleable nor ductile.
Non-Metals 3. Nonmetallic solids are neither malleable nor ductile. 4. Poor conductors of heat and electricity.

Non-Metals tend to gain e-.
Cl

Most Reactive Non-Metal
F I Fluorine Most Active Non-Metal

B Si Ge As Sb Te Po B Si Ge As Sb Te Po The seven metalloids are:

Metalloid Properties Characteristics in between that of the metals and the nonmetals. Sometimes they are good conductors of heat and electricity.

Variations across a Period
Less Metallic more Non-Metallic

Homework 5-2 Worksheet Due: 11/13/08

The electrons in the highest occupied energy level of an atom.
Valence Electrons The electrons in the highest occupied energy level of an atom.

Valence Electrons Elements in a group have similar properties because they have the same number of valence electrons..

Alkali Metals Alkaline Earth Metals Noble Gases Halogens Nitrogen
Boron Carbon Nitrogen Oxygen Halogens Alkaline Earth Metals

Li Na K Rb Cs Fr Alkali Metal Group 1A Very reactive metals.
Do not occur freely in nature. Only one electron in their outer shell. (1 valence Electron) Na K Rb Cs Fr Most reactive metal!!!!

Be Mg Ca Sr Ba Ra Alkaline Earth Metal Group 2A Very reactive
Not found free in nature. Two electron in their outer shell. (2 Valence Electron) Magnesium and Calcium important elements in life. Mg Ca Sr Ba Ra

B Al Ga In Tl Boron Family Group 3A
Three electrons in their outer shell. (3 Valence Electrons) Aluminum is the most abundant metal in the Earth’s crust. Al Ga In Tl

C Si Ge Sn Pb Carbon Family Four electrons in their outer shell.
Group 4A. Four electrons in their outer shell. (4 Valence Electrons) Consists of: One nonmetal (carbon) Two metals (tin and lead) Two metalloids (silicon and germanium). Except for water, most compounds in your body contain carbon. Si Ge Sn Pb

N P As Sb Bi Nitrogen Family Group 5A.
Five electrons in the outermost energy level. (5 Valence Electrons) They physical and chemical properties that are strikingly different. N and P make up fertilizer. P As Sb Bi

O S Se Te Po Oxygen Family Group 6A.
Six electrons in their outermost energy level. (6 Valence Electrons) Oxygen is the most abundant element in the earth’s crust. S Se Te Po

F Halogens Cl The halogens are five non-metallic elements found in group 7A of the periodic table. All halogens have 7 electrons in their outer shells. The halogens exist, at room temperature, in all three states of matter. Br I At

He Ne Ar Kr Xe Rn Noble Gases
The six noble gases are found in group 8A of the periodic table. These elements were considered to be inert gases. All noble gases have the maximum number of electrons possible in their outer shell (2 for Helium, 8 for all others), making them stable. Colorless/Odorless Gases Ne Ar Kr Xe Rn

Electron Dot Diagram Lewis Diagram
Symbol of the element Dots for Valence Electrons. (Outer most energy level Electrons) Cl Ne Na C

5-3: Worksheet Due: 11/14/08 Word-Wise & Math Due: 11/17/08
Homework 5-3: Worksheet Due: 11/14/08 Word-Wise & Math Due: 11/17/08 Test: 11/19/08

Test 11/20/07