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Chapter 6 Ionic Compounds Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Silence cell phones and pagers. Slide 2 Chapter 06 Slide 2 of 92 An octet Contains 8 valence electrons. Is associated with the stability of the noble gases. Exception is He that is stable with 2 valence electrons (duet). valence electrons He 22 (Exception) Ne 2, 88 Ar 2, 8, 8 8 Kr 2, 8, 18, 88 Octet Rule Slide 3 Chapter 06 Slide 3 of 92 Review: Valence Electrons The valence electrons Are the electrons in the s and p sublevels in the highest energy level. Are related to the Group number of the element. Determine the chemical properties of the elements. Elements with similar properties have the same number of ___________________ ! Slide 4 Chapter 06 Slide 4 of 92 Forming Octets Atoms acquire octets By losing, gaining, or sharing valence electrons. To form compounds. To become more stable. Slide 5 Chapter 06 Slide 5 of 92 Size of Sodium Ion The sodium ion Na + Forms when the Na atom loses one electron from the 3 rd energy level, its valence electron. Is smaller than a Na atom. Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Octet Slide 6 Chapter 06 Slide 6 of 92 Size of Fluoride Ion The fluoride ion F - Forms when a valence electron is added. Has increased repulsions due to the added valence electron. Is larger than F atom Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Octet Slide 7 Chapter 06 Slide 7 of 92 Ionic and Covalent Bonds Ionic bonds involve Loss of electrons by a metal. Gain of electrons by a nonmetal. Covalent bonds involve A sharing of electrons. Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 8 Chapter 06 Slide 8 of 92 Metals Form Positive Ions Metals form Octets by losing all of their valence electrons. Positive ions with the electron configuration of the nearest noble gas. Positive ions with fewer electrons than protons. Group 1A(1) metals ion 1+ Group 2A(2) metals ion 2+ Group 3A(13) metals ion 3+ Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 9 Chapter 06 Slide 9 of 92 Formation of a Sodium Ion, Na + Sodium achieves an octet by losing its one valence electron. Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings 2, 8, 1 2, 8 Slide 10 Chapter 06 Slide 10 of 92 Charge of Sodium Ion, Na + With the loss of its valence electron, the sodium ion has a 1+ charge. Sodium atom Sodium ion 11p + 11p + 11e - 10e - 0 1+ Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings 2, 8 Slide 11 Chapter 06 Slide 11 of 92 Formation of Mg 2+ Magnesium achieves an octet by losing its two valence electrons. Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings 2, 8, 2 2, 8 Slide 12 Chapter 06 Slide 12 of 92 Charge of Magnesium Ion Mg 2+ With the loss of two valence electrons, magnesium forms a positive ion with a 2+ charge. Mg atomMg 2+ ion 12p + 12p + 12e- 10e - 0 2+ Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings 2, 8 Slide 13 Chapter 06 Slide 13 of 92 Formation of Negative Ions In ionic compounds, nonmetals Achieve an octet arrangement. Gain electrons. Form negatively charged ions with 3-, 2-, or 1- charges. Slide 14 Chapter 06 Slide 14 of 92 Formation of Chloride Ion, Cl - Chlorine achieves an octet by adding an electron to its valence electrons. Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings 2, 8, 7 2, 8, 8 Slide 15 Chapter 06 Slide 15 of 92 Charge of a Chloride Ion, Cl - A chlorine ion forms When Cl gains one electron With a 1- charge. Chlorine atom Chloride ion 17p + 17p + 17e - 18e - 0 1 Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 16 Chapter 06 Slide 16 of 92 Some Ionic Charges Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings I-I- Slide 17 Chapter 06 Slide 17 of 92 Ionic Charge from Group Numbers The charge of a positive ion is equal to its Group number. Group 1A(1) = 1+ Group 2A(2) = 2+ Group 3A(13) = 3+ The charge of a negative ion is obtained by subtracting 8 or 18 from its Group number. Group 6A(16) = 6 - 8 = 2- or 16 - 18= 2- Slide 18 Chapter 06 Slide 18 of 92 Upon loss or gain of electons, the electronic arrangement of the ion is _____________ with its nearest noble gas. Slide 19 Chapter 06 Slide 19 of 92 An octet Is ___ valence electrons Is associated with the stability of the noble gases He is stable with ___ valence electrons (duet). valence electrons He 1s 2 __ Ne 1s 2 2s 2 2p 6 __ Ar 1s 2 2s 2 2p 6 3s 2 3p 6 __ Kr 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 __ Octet Rule - What is special about 8 ? Slide 20 Chapter 06 Slide 20 of 92 Learning Check Select the correct answer for Sodium 1A(1): 1. Number of ________________ A) ________ B) ________ C) ________ 2. Electron ________ to achieve ________ A) ________ B) ________ C) ________ 3. _____________ of sodium ion A) ________ B) ________ C) ________ 4. The ________ for the sodium ion A) ________ B) ________ C) ________ Slide 21 Chapter 06 Slide 21 of 92 Select the correct answer for nitrogen 5A(15): 5. Number of __________________ A) ________ B) ________ C) ________ 6.Change in ________ for ________ A) ________ B) ________ C) ________ 7. Ionic ________ of ________ A) ________ B) ________ C) ________ 8. The ________ for the ________ A) ________ B) ________ C) ________ Learning Check Slide 22 Chapter 06 Slide 22 of 92 Compounds - Compounds result from the formation of chemical bonds between two or more different elements. Slide 23 Chapter 06 Slide 23 of 92 Chemical bond: attractive force holding two or more atoms together. Slide 24 Chapter 06 Slide 24 of 92 Ionic Bonds - electron transfer process. Typically between a metal and a nonmetals Covalent Bonds - electrons shared. Typically involving nonmetals. Slide 25 Chapter 06 Slide 25 of 92 Ionic compounds Consist of positive and negative ions. Have ionic bonds between positively and negatively charged ions. Have high melting and boiling points. Are solid at room temperature. Ionic Compounds Slide 26 Chapter 06 Slide 26 of 92 Salt is An Ionic Compound Sodium chloride (table salt) is an example of an ionic compound. Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 27 Chapter 06 Slide 27 of 92 An ionic formula Consists of positively and negatively charged ions. Is neutral. Has charge balance. total positive charge = total negative charge Uses subscripts to indicate the number of ions needed to give charge balance. Ionic Formulas Slide 28 Chapter 06 Slide 28 of 92 Ionic Formula of NaCl In an ionic formula The symbol of the metal is written first followed by the symbol of the nonmetal. The charges of the ions in the compound are not shown. Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 29 Chapter 06 Slide 29 of 92 The formulas of ionic compounds are determined from the charges on the ions. atoms ions Na + F : Na + : F : NaF sodium fluorine sodium fluoride The overall charge of NaF is zero (0). Na + F - = NaF (1+ ) + (1-) = 0 Charge Balance in NaF Slide 30 Chapter 06 Slide 30 of 92 Charge Balance In MgCl 2 In forming MgCl 2 A Mg atom loses two valence electrons. Two Cl atoms each gain one electron. Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 31 Chapter 06 Slide 31 of 92 Using Lewis Electron Dot Symbols Br Mg + Br Slide 32 Chapter 06 Slide 32 of 92 Using Lewis Electron Dot Symbols Al + N Slide 33 Chapter 06 Slide 33 of 92 Writing Ionic Formulas from Charges Charge balance is used to write the formula for sodium nitride, a compound containing Na + and N 3. Na + 3Na + +N 3 = Na 3 N Na + 3(+1) + 1(3-) = 0 Note: the subscript 3 for three sodium ions. Slide 34 Chapter 06 Slide 34 of 92 Write the ionic formula of the compound with Ba 2+ and Cl . Write the symbols of the ions. Ba 2+ Cl Balance the charges. Ba 2+ Cl two Cl - needed Cl Write the ionic formula using a subscript 2 for two chloride ions. BaCl 2 Formula from Ionic Charges Slide 35 Chapter 06 Slide 35 of 92 Write the correct formula for the ionic compounds formed by the following ions: 1. 2. 3. Learning Check Slide 36 Chapter 06 Slide 36 of 92 Naming and Writing Ionic Formulas Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 37 Chapter 06 Slide 37 of 92 Naming of Ionic Compounds In the name of an ionic compound The positive ion (first ion) is named as the element. The negative ion (second ion) is named by changing the end of the element name to ide. Slide 38 Chapter 06 Slide 38 of 92 Names of Some Common Ions 3A (13) Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 39 Chapter 06 Slide 39 of 92 Complete the names of the following ions: Ba 2+ Al 3+ K + _________ __________ _________ N 3 O 2 F _________ ___________________ P 3 S 2 Cl _________ __________ _________ Learning Check Slide 40 Chapter 06 Slide 40 of 92 To name a compound that contains two elements Identify the cation and anion. Name the positive metal ion (cation) as the element. Name the anion by changing the ending to ide. Name the cation first followed by the name of the anion. Naming Ionic Compounds with Two Elements Slide 41 Chapter 06 Slide 41 of 92 Charges of Representative Elements Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 42 Chapter 06 Slide 42 of 92 Formula IonsName NaClNa + Cl - sodium chloride K 2 SK + S 2- potassium sulfide MgOMg 2+ O 2- magnesium oxide CaI 2 Ca 2+ I - calcium iodide Al 2 O 3 Al 3+ O 2- aluminum oxide Some Ionic Compounds with Two Elements Slide 43 Chapter 06 Slide 43 of 92 More Ionic Compounds Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 44 Chapter 06 Slide 44 of 92 Write the formulas and names for compounds of the following ions: N 3 Br S 2 Na + Al 3+ Slide 45 Chapter 06 Slide 45 of 92 Write the names of the following compounds: 1) CaO___________ 2) KBr___________ 3) Al 2 O 3 ___________ 4) MgCl 2 ___________ Slide 46 Chapter 06 Slide 46 of 92 Most Transition Metals form Two or More Positive Ions Most of the transition metals Form 2 or more positive ions. For example, Copper forms Cu + and Cu 2+ Iron forms Fe 2+ and Fe 3+ Gold form Au + and Au 3+ Slide 47 Chapter 06 Slide 47 of 92 Metals that form more than One Cation Some Metals That Form More Than One Positive Ion Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Lead Pb 2+ lead(II) Pb 4+ lead(IV) Slide 48 Chapter 06 Slide 48 of 92 Periodic Table and Some Ions Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 49 Chapter 06 Slide 49 of 92 Naming Variable Charge Metals Transition metals With two different ions use a Roman numeral after the name of the metal to indicate ionic charge. Only zinc, silver, and cadmium form one ion (Zn 2+, Ag +, and Cd 2+ ) Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 50 Chapter 06 Slide 50 of 92 Naming FeCl 2 To name FeCl 2 [ 1 Iron ion + 2 chloride ions ] 1. Determine the charge of the cation using the charge of the anion (Cl - ). Fe ion + 2 Cl - = 1(?) + 2(1-) = 0 Fe ion = 2+ Fe 2+ 2. Name the cation by the element name and a Roman numeral in parenthesis to show charge. Fe 2+ = iron(II) 3. Write the name of the anion with an ide ending. iron(II) chloride = FeCl 2 Slide 51 Chapter 06 Slide 51 of 92 Naming Cr 2 O 3 To name Cr 2 O 3 1. Determine the charge of cation from the anion (O 2- ). 2Cr ions + 3 O 2- = ? + 3(2-) = ? - 6 = 0 ? = +6 +6/ 2Cr ions = +3 Cr ion = 3+ Cr 3+ 2. Name the cation by the element name and use a Roman numeral in parenthesis to show its charge. Cr 3+ = chromium(III) 3. Write the name of the anion with -ide ending. chromium(III) oxide = Cr 2 O 3 Slide 52 Chapter 06 Slide 52 of 92 Learning Check Select the correct name for each. 1. 2. Slide 53 Chapter 06 Slide 53 of 92 Writing Formulas Write the formula of potassium sulfide. STEP 1Identify the cation and anion. potassium = K + sulfide = S 2 STEP 2. Balance the charges. K + S 2 K + 2(1+) + 2(1-) = 0 STEP 3. 2 K + and 1 S 2 = K 2 S Slide 54 Chapter 06 Slide 54 of 92 Writing Formulas Write the formula of cobalt(III) chloride. STEP1. Identify the cation and anion. cobalt(III) = Co 3+ (III = charge of 3+) chloride = Cl STEP 2. Balance the charges. Co 3+ Cl Cl = (3+) + 3(1-) = 0 Cl STEP 3. 1 Co 3+ and 3 Cl = CoCl 3 Slide 55 Chapter 06 Slide 55 of 92 Learning Check The correct formula for each of the following is: 1. 2. Slide 56 Chapter 06 Slide 56 of 92 Polyatomic Ions Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 57 Chapter 06 Slide 57 of 92 A polyatomic ion Is a group of atoms. Has an overall ionic charge. Some examples of polyatomic ions are NH 4 + ammoniumOH hydroxide NO 3 nitrateNO 2 nitrite CO 3 2 carbonatePO 4 3 phosphate HCO 3 hydrogen carbonate (bicarbonate) Polyatomic Ions Slide 58 Chapter 06 Slide 58 of 92 Some Compounds with Polyatomic Ions Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 59 Chapter 06 Slide 59 of 92 The names of common polyatomic anions End in ate. NO 3 nitratePO 4 3 phosphate With one oxygen less end in ite. NO 2 nitritePO 3 3 phosphite With hydrogen attached use prefix hydrogen (or bi). HCO 3 hydrogen carbonate (bicarbonate) HSO 3 hydrogen sulfite (bisulfite) More Names of Polyatomic Ions Slide 60 Chapter 06 Slide 60 of 92 Names and Formulas of Common Polyatomic Ions Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 61 Chapter 06 Slide 61 of 92 Names and Formulas of Common Polyatomic Ions Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 62 Chapter 06 Slide 62 of 92 Polyatomic ions of the halogens require prefixes. ClO 4 perchlorateone oxygen more ClO 3 chlorate most common form ClO 2 chloriteone oxygen less ClO hypochlorite two oxygens less Prefixes for Names of Polyatomic Ions of Halogens Slide 63 Chapter 06 Slide 63 of 92 The positive ion is named first followed by the name of the polyatomic ion. NaNO 3 sodium nitrate K 2 SO 4 potassium sulfate Fe(HCO 3 ) 3 iron(III) bicarbonate or iron(III) hydrogen carbonate (NH 4 ) 3 PO 3 ammonium phosphite Naming Compounds with Polyatomic Ions Slide 64 Chapter 06 Slide 64 of 92 Some Compounds with Polyatomic Ions Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 65 Chapter 06 Slide 65 of 92 Naming Polyatomic Ions Nick the Camel Craved and ate a Clam Supper in Phoenix. Slide 66 Chapter 06 Slide 66 of 92 Select the correct formula for each: 1. 2. 3. 4. Learning Check Slide 67 Chapter 06 Slide 67 of 92 Match each formula with the correct name: A) magnesium sulfite B) magnesium sulfate C) magnesium sulfide Learning Check Slide 68 Chapter 06 Slide 68 of 92 Learning Check A) calcium chlorate B) calcium chlorite C) calcium hypochlorite Slide 69 Chapter 06 Slide 69 of 92 Learning Check Name each of the following compounds: 1. Mg(NO 3 ) 2 2.Cu(ClO 3 ) 2 3.PbO 2 4.Fe 2 (SO 4 ) 3 5.Ba 3 (PO 3 ) 2 Slide 70 Chapter 06 Slide 70 of 92 Writing Formulas with Polyatomic Ions The formula of an ionic compound Containing a polyatomic ion must have a charge balance that equals zero(0). Na + and NO 3 NaNO 3 With two or more polyatomic ions encloses the polyatomic ions in parentheses. Mg 2+ and 2NO 3 Mg(NO 3 ) 2 subscript 2 for charge balance Slide 71 Chapter 06 Slide 71 of 92 Learning Check Write the correct formula for each: 1.potassium bromate 2.calcium carbonate 3.sodium phosphate 4.iron(III) oxide 5.iron(II) nitrite Slide 72 Chapter 06 Slide 72 of 92 Naming Ionic Compounds Review: Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 73 Chapter 06 Slide 73 of 92 Flowchart for Naming Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 74 Chapter 06 Slide 74 of 92 Learning Check Name the following compounds: A. Ca 3 (PO 4 ) 2 B. FeBr 3 C. Al 2 S 3 D. Mn(NO 2 ) 2 E. NaHCO 3 Slide 75 Chapter 06 Slide 75 of 92 Learning Check Write the formulas for the following: A. calcium nitrate B. iron(II) hydroxide C. aluminum carbonate D. copper(II) hypobromite E. lithium phosphate Slide 76 Chapter 06 Slide 76 of 92 Covalent Compounds and Their Names Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 77 Chapter 06 Slide 77 of 92 Forming a H 2 Molecule Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 78 Chapter 06 Slide 78 of 92 H 2, A Covalent Molecule In a hydrogen (H 2 ) molecule Two hydrogen atoms share electrons to form a covalent single bond. Each H atom acquires two (2) electrons. Each H becomes stable like helium (He). Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 79 Chapter 06 Slide 79 of 92 Diatomic Elements These elements share electrons to form diatomic covalent molecules or molecular elements Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 80 Chapter 06 Slide 80 of 92 Electron-Dot Formulas Electron-dot formulas show The order of bonded atoms in a covalent compound. The bonding pairs of electrons between atoms. The unshared (lone) valence electrons if they exist. A central atom with an octet. Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 81 Chapter 06 Slide 81 of 92 Electron-Dot Formulas and Models of Some Covalent Compounds Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 82 Chapter 06 Slide 82 of 92 Names of Covalent Compounds Prefixes are used In the names of covalent compounds. Because typically two nonmetals can form two or more different compounds. Examples of compounds of N and O: NO nitrogen oxide NO 2 nitrogen dioxide N 2 O dinitrogen oxide N 2 O 4 dinitrogen tetroxide N 2 O 5 dinitrogen pentoxide Slide 83 Chapter 06 Slide 83 of 92 Naming Covalent Compounds STEP 1 Name the first nonmetal as the element. STEP 2 End the name of the second nonmetal with -ide STEP 3 Use prefixes to show the number of atoms (subscripts). Mono is usually omitted. Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 84 Chapter 06 Slide 84 of 92 What is the name of SO 3 ? STEP 1 The first nonmetal is S sulfur. STEP 2 The second nonmetal is O named oxide. STEP 3 The subscript 3 of O is shown as the prefix tri. SO 3 sulfur trioxide The subscript 1(for S) or mono is understood. Naming Covalent Compounds Slide 85 Chapter 06 Slide 85 of 92 Name P 4 S 3 STEP 1 The first nonmetal P is phosphorus. STEP 2 The second nonmetal S is sulfide. STEP 3 The subscript 4 of P is shown as tetra. The subscript 3 of S is shown as tri. P 4 S 3 tetraphosphorus trisulfide Naming Covalent Compounds Slide 86 Chapter 06 Slide 86 of 92 Formulas and Names of Some Covalent Compounds Copyright 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings Slide 87 Chapter 06 Slide 87 of 92 Select the correct name for each compound. A.SiCl 4 1) 2) 3) B. P 2 O 5 1) 2) 3) C.Cl 2 O 7 1) 2) 3) Learning Check Slide 88 Chapter 06 Slide 88 of 92 Write the name of each covalent compound: CO CO 2 PCl 3 CCl 4 N 2 O Learning Check Slide 89 Chapter 06 Slide 89 of 92 STEP 1 Write the symbols in the order of the elements in the name. STEP 2 Write any prefixes as subscripts. Example: Write the formula for carbon disulfide. STEP 1 Elements are C and S STEP 2 No prefix for carbon means 1 C Prefix di = 2 Formula: CS 2 Guide to Writing Formulas Slide 90 Chapter 06 Slide 90 of 92 Write the correct formula for each of the following: A. phosphorus pentachloride B. dinitrogen trioxide C. sulfur hexafluoride Learning Check Slide 91 Chapter 06 Slide 91 of 92 Learning Check Identify each compound as ionic or covalent and give its correct name. 1. SO 3 2. MnCl 2 3. (NH 4 ) 3 PO 3 4. Cu 2 CO 3 5. N 2 O 4 Slide 92 Chapter 06 Slide 92 of 92 Learning Check Identify each compound as ionic or covalent and give its correct name. 1.Ca 3 (PO 4 ) 2 2.FeBr 3 3.SCl 2 4.Cl 2 O