UNIT 3: BONDING

ESSENTIAL STANDARDS Chm.1.2 Understand the bonding that occurs in simple compounds in terms of bond type, strength, and properties. Chm Compare (qualitatively) the relative strengths of ionic, covalent, and metallic bonds. Chm Infer the type of bond and chemical formula formed between atoms. Chm Compare inter- and intra- particle forces. Chm Interpret the name and formula of compounds using IUPAC convention. Chm Compare the properties of ionic, covalent, metallic, and network compounds.

Summarize HOW AND WHY DO ELEMENTS BOND? HOW DO YOU WRITE CHEMICAL FORMULAS?

WHAT DO I NEED TO KNOW FROM MY PAST?

TRENDS

E- DOT DIAGRAMS

VALENCE

ANALOGY ATOM : ELEMENT :: MOLECULE : COMPOUND

COMPOUND 2 OR MORE DIFFERENT ELEMENTS CHEMICALLY COMBINED CAN’T SEPARATE PHYSICALLY

I. BONDING WHAT IS THE GOAL IN BONDING?

A) IONIC

ANION VS. CATION

B) COVALENT

C) OXIDATION NUMBERS THE NUMBER OF ELECTRONS AN ATOM MUST GAIN/LOSE OR SHARE TO FORM A FULL OUTER SHELL RELATE TO VALENCE…

II. 4 MAIN TYPES OF REACTIONS SYNTHESIS

DECOMPOSITION

SINGLE DISPLACEMENT

DOUBLE DISPLACEMENT

III. NOMENCLATURE NAMING COMPOUNDS IUPAC: International Union of Pure and Applied Chemistry: world authority on nomenclature, termininology, standards of measurements, etc. A) METALS/NONMETAL p. 86 **BINARY COMPOUNDS B) BINARY COMPOUNDS WITH TRANSITION ELEMENTS PAGE 89 C) BINARY COMPOUNDS WITH NONMETALS D) WITH POLYATOMIC IONS

NCFE REFERENCE TABLES YOU WILL GET THIS ON NCFE

F) Acids *These begin with an H *2 groups: Binary acids and Oxyacids

1. Binary Acids Name = 2 words First word has 3 parts: hydro + root of nonmetal elem + ic Second word is “acid” HF HCl HBr

2. Oxyacids-made of hydrogen, nonmetal and oxygen First word is most difficult… “ate” ions (sulfate, nitrate, phosphate, etc. ) make “ic” acids (sulfuric acid, nitric acid, phosphoric acid) Use the “ate” ion as a point of reference One more oxygen than –ic acid is called a per__ic acid One less oxygen than –ic acid is called ____ous acid One less oxygen that the –ous acid is called hypo ___ ous acid

You may see binary acid and ternary acid. Binary acids have 2 elements Ternary acids have 3 element and the 3 rd one is oxygen

f) bases Metal + OH Exs. Sodium hydroxide calcium hyroxide Exception: ammonia --- _______

IV. Properties based on bonding Can you use the periodic table to PREDICT the type of bonding?

a) IONIC Made of crystals (called crystal lattice) High melting point, high boiling point Often water soluble Shatter when struck Conduct electricity in water (good conductor in liquid) Poor conductor in solid

IONIC Because opposites attract (cation/anion), it takes a lot of energy to separate these ionic bonds…so these have a stronger bond than covalently bonded compounds.

b) COVALENT Low melting points and low boiling points Soft and pliable, usually won’t shatter Poor conductors of heat and electricity Most are poor soluble in water

Polar and Nonpolar Covalent Bonds Polar: when electrons are not shared equally Nonpolar: when electrons are shared equally

c) METALLIC Imagine dropping a ton of golf balls into a bathtub…they will organize themselves evenly…that’s what happens in a metallic bond…they form a “sea of electrons” and there is sharing of electrons all around Malleable Ductile Conduct heat Ex. metals in jewelry, coins, weapons