The Periodic Table

Atomic Number (number of protons) Symbol Atomic Mass Period

The Periodic Table Groups are based on number of valence electrons (electrons in the outer shell or energy level) of each element

The Periodic Table Dot Diagrams

The Periodic Table

Patterns of Valence Electrons Lithium Atomic Number (number of protons) Period Symbol Atomic Mass

Patterns of Valence Electrons Number of Energy Levels: 2 First Energy Level: 2 Second Energy Level: 1 Lithium

Patterns of Valence Electrons Beryllium Atomic Number (number of protons) Symbol Atomic Mass Period

Patterns of Valence Electrons Number of Energy Levels: 2 First Energy Level: 2 Second Energy Level: 2 Beryllium

Patterns of Valence Electrons Boron Atomic Number (number of protons) Symbol Atomic Mass Period

Patterns of Valence Electrons Boron Number of Energy Levels: 2 First Energy Level: 2 Second Energy Level: 3

Patterns of Valence Electrons Sodium Atomic Number (number of protons) Symbol Atomic Mass Period

Patterns of Valence Electrons Sodium Number of Energy Levels: 3 1 st Energy Level: 2 2 nd Energy Level: 8 3 rd Energy Level: 1

Patterns of Valence Electrons Number of Energy Levels: 4 1 st Energy Level: 2 2 nd Energy Level: 8 3 rd Energy Level: 8 4 th Energy Level: 1

Patterns of Valence Electrons Number of Energy Levels: 5 1 st Energy Level: 2 2 nd Energy Level: 8 3 rd Energy Level: 18 4 th Energy Level: 8 5 th Energy Level: 1

Patterns of Valence Electrons Number of Energy Levels: 6 1 st Energy Level: 2 2 nd Energy Level: 8 3 rd Energy Level: 18 4 th Energy Level: 18 5 th Energy Level: 8 6 th Energy Level: 1

Patterns of Valence Electrons Number of Energy Levels: 7 1 st Energy Level: 2 2 nd Energy Level: 8 3 rd Energy Level: 18 4 th Energy Level: 32 5 th Energy Level: 18 6 th Energy Level: 8 7 th Energy Level: 1

The Periodic Table A row of elements across the periodic table is called a Period The atomic number increases one at a time across a period of elements

The Periodic Table Period 2 starts with Lithium Period 2 and continues across to Neon

The Periodic Table

Elements with the same number of valence electrons have similar properties

The Periodic Table For example, lithium, sodium,

The Periodic Table For example, lithium, sodium, and the rest of the elements in Group 1 are all alkali metals which are very reactive Alkali Metals

The Periodic Table GROUP 1

The Periodic Table GROUP 1 Alkali Metals 1 Valence electron in outer shell. Very REACTIVE

The Periodic Table GROUP 18 NOBEL GASES

The Periodic Table GROUP 18 NOBEL GASES 8 Valence Electrons in outer shell. Very Stable

The Periodic Table GROUP 17 HALOGENS

The Periodic Table GROUP 17 HALOGENS 7 Valence Electrons in outer shell. Very Reactive

The Periodic Table Other metals Groups 2 through 12

The Periodic Table Most have 1, 2, or 3 Valence electrons

The Periodic Table They react by losing electrons

The Periodic Table Other Nonmetals (Green)

The Periodic Table React by gaining electrons

The Periodic Table Metalloids (Yellow)

The Periodic Table Behave as metals or nonmetals

The Periodic Table Can lose or share electrons

The Periodic Table Hydrogen

The Periodic Table Considered a nonmetal

The Periodic Table Located above Group 1

The Periodic Table One valence electron

The Periodic Table Very REACTIVE

The Periodic Table QUESTIONS?

Chemical Formulas and Names What is a chemical formula? Compounds can be represented by chemical formulas

Chemical Formulas and Names A chemical formula is a combination of symbols that shows the ratio of elements in a compound.

Chemical Formulas and Names Formulas of Ionic Compounds MgCl 2 The formula for magnesium chloride.

Chemical Formulas and Names Formulas of Ionic Compounds MgCl 2 (Magnesium Chloride) One Magnesium ion Two Chloride ions

Chemical Formulas and Names Formulas of Ionic Compounds MgCl 2 Mg Cl 2+ 1-

Chemical Formulas and Names Formulas of Ionic Compounds NaCl One Sodium ion One Chloride ion

Chemical Formulas and Names Formulas of Ionic Compounds NaCl Na Cl 1+ 1-

Chemical Formulas and Names Naming Ionic Compounds The name of the positive ion comes first… Followed by the name of the negative ion

Chemical Formulas and Names Naming Ionic Compounds If the negative ion is a single element the end of its name changes to -ide MgO = Magnesium Oxide NaCl = Sodium Chloride

Chemical Formulas and Names Naming Ionic Compounds If the negative ion is a polyatomic element the end of its name changes to –ate or -ite NH 4 NO 3 = Ammonium Nitrate

Ionic Compounds They have opposite charges and opposite charges attract Why do sodium and chloride ions bond together?

Ionic Compounds General Properties or Characteristics of Ionic Compounds High melting points Conduct electricity when dissolved or melted Hard, brittle crystals Energy is required to break ionic bonds

Ionic Compounds What are Ionic compounds? Ionic compounds are compounds that consist of positive and negative compounds

Molecular Compounds What are Molecular compounds? Molecular compounds are compounds that contain molecules bonded with COVALENT bonds

Covalent Bonds What is a covalent bond? The chemical bond formed when two atoms share electrons

How Covalent Bonds Form

Covalent bonds usually form between atoms of nonmetals Ionic Compounds vs Molecular Compounds Ionic bonds usually form when a metal combines with a nonmetal

In Ionic bonding, atoms give up or gain an electron Ionic Compounds vs Molecular Compounds In covalent bonding, atoms share electrons

NaCl Na Cl Ionic Compounds vs Molecular Compounds Ionic Bonding

Ionic Compounds vs Molecular Compounds Covalent Bonding

Covalent Bonds What is a covalent bond? The chemical bond that forms when two atoms share electrons

Covalent Bonds H H Hydrogen Atom Oxygen Atom Water Molecule with two covalent bonds

Covalent Bonds How many covalent bonds can an atom form? Oxygen has 6 valence electrons so it can form 2 covalent bonds

Covalent Bonds How many covalent bonds can an atom form? The exception is Hydrogen which only needs two electrons to be complete H

Covalent Bonds How many covalent bonds can an atom form? Each Hydrogen atom can form one bond because it only needs 2 electrons to be stable H

Covalent Bonds H H H Hydrogen Atoms Nitrogen Atom

Covalent Bonds H H H Ammonia molecule… Three covalent bonds

Covalent Bonds Double and Triple Bonds Oxygen Atom

Covalent Bonds Double and Triple Bonds Oxygen Molecule

Covalent Bonds Double and Triple Bonds Go to page 32 of your textbook