BONDING UNIT TIER 1 Define a bond   TIER 1 Define a bond Define ion as well as cation and anion Compare and contrast ionic, covalent and metallic bonding TIER 2 Deduce which ions form when elements in Groups 1,2 & 3 lose electrons Deduce which ions form when elements in Groups 5,6, & 7 gain electrons Explain which ions form when transition metals lose electrons TIER 3 Apply electronegativity values and the position of two elements on the periodic table to determine the type of dominant bonding that occurs; ionic, polar covalent or nonpolar covalent Describe the lattice structure of ionic compounds and apply this to explain the physical properties of ionic compounds Describe the model of metallic bonding and apply this to explain the physical properties of metals State and explain the relationship between number of bonds, bond length and bond strength. TIER 4 Deduce the Lewis structures of molecules and ions for up to four electrons pairs on each atom Predict the shape and bond angles for species with four, three and two negative charge centers on the center atom using the valence shell electron pair repulsion theory (VSEPR) Analyze the physical properties of covalent compounds resulting from single, double and triple bonds Describe and compare the structure and bonding in the three allotropes of carbon; diamond, graphite and fullerene. Describe the structure and bonding of silicon and silicon dioxide TIER 5 Evaluate the type of intermolecular forces that occurs between covalent molecules based on the structural features of the molecules Evaluate how the intermolecular forces affect the boiling points of substances TIER 6 Design a lab that shows a trend in a physical property of substances that are either ionic, covalent or metallic. ( This will be your first official IA lab for IB submission)

TIER 1 Define a bond Define ion as well as cation and anion Compare and contrast ionic, covalent and metallic bonding

WHAT IS A BOND? Any of several forces, especially the ionic bond, covalent bond, and metallic bond, by which atoms or ions are bound in a molecule or crystal.

IONS CATION OR ANION An ion is a charged atom that has either gained or lost electrons A cation is a positively charged ion that has lost electrons An anion is a negatively charged ion that has gained electrons ***REMEMBER: The charge is from the uneven distribution of electrons to protons and since electrons are negatively charges and protons are positively charge, if there are more electrons than protons then the ion will be negatively charged and if there are more protons than electrons then the ion will be positively charged. The charge DOES NOT refer to the gain or lose of electron. CHARGE IS NOT A MATHEMATICAL SIGN

IONIC, COVALENT OR METALLIC BONDING Involves a lattice of cations with delocalized electrons The electrons are free to move within the lattice forming a “sea of electrons” The strength of the bond depends on the charge of the ions and the radius of the metal ion IONIC BONDING Involves a transfer of electrons The ions are held together by the electrostatic attraction between oppositely charged ions The ions are held together in lattice structures Under normal conditions ionic compounds are usually solids COVALENT BONDING Involves the sharing of electrons The bond is formed by electrostatic attraction between the shared pairs of electrons and the positively charged nuclei

TIER 2 Deduce which ions form when elements in Groups 1,2 & 3 lose electrons Deduce which ions form when elements in Groups 5,6, & 7 gain electrons Explain which ions form when transition metals lose electrons

GROUPS 1,2 & 3 ELEMENTS GROUP 3 GROUP 1 GROUP 2 This family is sometimes referred to as the Boron family. This group consist of boron , a metalloid, and the other elements Al to Tl which are metals All can form 3+ cations. However, Indium and Thallium can also form 1+ ions. The most common ion for Indium is 3+ but the most common ion for Thallium is 1+ . GROUP 1 Called Alkali metals Form cations with 1+ charge GROUP 2 Called Alkaline Earth metals Form cations with a 2+ charge

GROUP 5,6 & 7 GROUP 5 GROUP 6 GROUP 7 This group contains the nonmetals, Nitrogen and Phosphorus, the metalloids, Arsenic & Antimony and the metal, Bismuth Both N & P from 3- anions in ionic compounds. There oxidation states can also be 3+ & 5+ Both As & Sb have 3-, 3+ & 5+ oxidation states Bismuth forms 3+ & 5+ cations GROUP 6 The most common oxidation state is -2, however oxygen can also exist as -1 in the case of peroxides . Sulfur can also exist at a +4 and +6 state and +2, +4, and +6 oxidation states are possible for Se, Te, and Po. GROUP 7 Referred to as Halogen. Hal means “salt” and gen means “to form” Tend to gain electrons to form 1- anions Can share electrons with other atoms and can have positive oxidation numbers

TRANSITION METALS Referred to as “d block” metals Also called multivalent metals due to the fact that most will form cations with more than one oxidation number For example, Iron can either be Fe 2+ or Fe 3+ Zinc, cadmium and silver however are not multivalent. Zn & Cd are 2+ and Ag is 1+ The name of the compound formed by transition metals and nonmetals will have a Roman numeral to designate the charge of the transition cation Tend to form colored compounds