Chapter 7 & 8 Nomenclature Notes/Study Guide. Properties of ionic bonds & compounds. Section 7-2

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1 Objectives Properties of ionic bonds & compounds Section 72 Define chemical bond. Describe formation of ionic bonds structure of ionic compounds. Generalize of ionic bonds based on Main Idea of ionic compounds Ions form when atoms gain or lose electrons achieving a stable. Oppositely charges ion each other, forming electrically neutral ionic compounds. Review Vocabulary Compound: a chemical combination of two or more different elements Octet rule: atoms tend to gain, lose, or share electrons in order to acquire eight valence electrons Ionic bond Ionic compound Crystal lattice Electrolyte Lattice energy Chemical bond Cation Anion Metals valence electrons easily. Metals become 1

2 Transition metals can form a of cations. Atoms that one or more electrons become charged A positively charged ion is called a. Atoms become one or more electrons charged 2

3 Anions Nonmetal ions usually required to fill an. the number of electrons Some nonmetals may or electrons to complete an octet. What s the Big Idea? Learning Oxygen gains two electrons to form what kind of ion? A. 1 anion C. 1+ cation B. 2 anion D. 2+ cation Elements with a full octet have which configuration? A. ionic configuration B. halogen configuration C. noble gas configuration D. transition metal configuration The force that holds oppositely charged particles together in an ionic compound is called an ionic bond. Particles held together by ionic are called ionic. Binary ionic compounds contain only two elements a & a. The repeating of in an ionic compound is called an ionic crystal. 3

4 There are other repeating patterns of particle packing for ionic compounds. Strong attractions among positive and negative ions result in the formation of. When particles are arranged in a shape is formed. Ionic Electrical Conductivity Solid ions are in place & electrons cannot move conductor. Liquid ions are locked in place & electrons can move they can conduct. Aqueous (dissolved in water) ions have electrons free to they conduct electricity. An ion in aqueous solution that conducts electricity is an. How and why crystals break when an external force is applied. 4

5 The energy required to 1 mole of ions in an ionic compound is referred to as the lattice energy. Lattice energy is directly related to the of the ions that are bonded. Smaller ions form compounds with more spaced ionic charges, and require more energy to separate. The the ion, the the attraction. Electrostatic force of attraction is related to the distance between the opposite charges. Melting point, boiling point, and hardness depend on the attraction. of the 5

6 What s the Big Idea? 6

7 Ionic Compounds composed of positive and usually formed from a these elements are ions. and nonmetal. attached to one another. Examples A formula unit is the whole number of ions in an ionic compound. i.e. Na 2 Cl 2 NaCl The smallest representative unit of an ionic compound There is such thing as a of NaCl!!!!!!!!! Binary means ` elements Writing Formulas charges must balance so charge is. Writing Formulas from Names 1st word = 2nd word = name with ide ending. Polyatomic Ions Definitiontightly bound groups of atoms that behave as a charge. and carry a Example 7

8 Names and Charges of Some Common Polyatomic Ions Cations (positive charge) 1. ammonium, NH hydronium H 3 O + Anions (negative charge) 3. acetate C 2 H 3 O 2 4. chlorate ClO 3 5. cyanide CN 6. hydrogen carbonate HCO 3 7. hydrogen sulfide HS 8. hydroxide OH 9. nitrate NO nitrite NO permanganate MnO carbonate 2 CO chromate 2 CrO dichromate 2 Cr 2 O oxalate 2 C 2 O peroxide 2 O sulfate 2 SO sulfite 2 SO phosphate PO 4 3 Practice 8