Naming Simple Compounds

Ionic Compounds Ionic compounds consist of positive and negative ions. have attractions called ionic bonds between positively and negatively charged ions. have high melting and boiling points. are solid at room temperature. Copyright Houghton Mifflin Company. All rights reserved. 2 2

Salt is An Ionic Compound Sodium chloride or table salt is an example of an ionic compound. Copyright 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings Copyright Houghton Mifflin Company. All rights reserved. 2 3

Naming Ionic Compounds with Two Elements To name a compound that contains two elements, identify the cation and anion. name the cation first followed by the name of the anion. Copyright Houghton Mifflin Company. All rights reserved. 2 4

Binary Ionic Compounds Type (I) An ionic formula consists of positively and negatively charged ions. is neutral. has charge balance. total positive charge = total negative charge The symbol of the metal is written first followed by the symbol of the nonmetal. Copyright Houghton Mifflin Company. All rights reserved. 2 5

Charge Balance In MgCl 2 In MgCl 2, a Mg atom loses two valence electrons. two Cl atoms each gain one electron. subscripts indicate the number of ions needed to give charge balance. Copyright 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings Copyright Houghton Mifflin Company. All rights reserved. 2 6

Charge Balance in Na 2 S In Na 2 S. two Na atoms lose one valence electron each. one S atom gains two electrons. subscripts show the number of ions needed to give charge balance. Copyright 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings Copyright Houghton Mifflin Company. All rights reserved. 2 7

Writing Ionic Formulas from Charges Charge balance is used to write the formula for sodium nitride, a compound containing Na + and N 3. Na + 3 Na + + N 3 = Na 3 N Na + 3(+1) + 1(3-) = 0 Copyright Houghton Mifflin Company. All rights reserved. 2 9

Formula from Ionic Charges 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 that give charge balance. BaCl 2 Copyright Houghton Mifflin Company. All rights reserved. 2 11

Learning Check Select the correct formula for each of the following ionic compounds. A. Na + and S 2-1) NaS 2) Na 2 S 3) NaS 2 B. Al 3+ and Cl - 1) AlCl 3 2) AlCl 3) Al 3 Cl C. Mg 2+ and N 3-1) MgN 2) Mg 2 N 3 3) Mg 3 N 2 Copyright Houghton Mifflin Company. All rights reserved. 2 12

Solution A. Na + and S 2-2) Na 2 S check: 2Na + + S 2- = 2(1+) + 1(2-) = 0 B. Al 3+ and Cl - 1) AlCl 3 check: Al 3+ + Cl - = (3+) + 3(1-) = 0 C. Mg 2+ and N 3-3) Mg 3 N 2 check: 2Mg 2+ +2N 3- = 2(3+) + 2(3-) = 0 Copyright Houghton Mifflin Company. All rights reserved. 2 13

Examples of Ionic Compounds with Two Elements Formula Ions Name cation anion NaCl Na + Cl - sodium chloride K 2 S K + S 2- potassium sulfide MgO Mg 2+ O 2- magnesium oxide CaI 2 Ca 2+ I - calcium iodide Al 2 O 3 Al 3+ O 2- aluminum oxide Copyright Houghton Mifflin Company. All rights reserved. 2 16

Solution Br S 2 N 3 NaBr Na 2 S Na 3 N Na + sodium bromide sodium sulfide sodium nitride Al 3+ AlBr 3 aluminum bromide Al 2 S 3 aluminum sulfide AlN aluminum nitride Copyright Houghton Mifflin Company. All rights reserved. 2 18

Binary Ionic Compounds (Type II) Transition Metals form Positive Ions Most transition metals and Group 4(14) metals form 2 or more positive ions. Zn 2+,Ag +, and Cd 2+ form only one ion. Copyright Houghton Mifflin Company. All rights reserved. 2 19

Metals that form more than One Cation The name of metals with two or more positive ions (cations) use a Roman numeral to identify ionic charge. Lead Pb 2+ lead(ii) Pb 4+ lead(iv) Copyright 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings Copyright Houghton Mifflin Company. All rights reserved. 2 20

Naming Variable Charge Metals Transition metals with two different ions use a Roman numeral after the name of the metal to indicate ionic charge. Copyright Houghton Mifflin Company. All rights reserved. 2 22

Naming FeCl 2 To name FeCl 2 1. Determine the charge of the cation using the charge of the anion (Cl - ). Fe ion + 2 Cl - = Fe ion + 2- = 0 Fe ion = 2+ 2. Name the cation by the element name and add a Roman numeral in parenthesis to show its charge. Fe 2+ = iron(ii) 3. Write the anion with an ide ending. FeCl 2 = iron(ii) chloride Copyright Houghton Mifflin Company. All rights reserved. 2 23

Naming Cr 2 O 3 To name Cr 2 O 3 1. Determine the charge of cation from the anion (O 2- ). 2 Cr ions + 3 O 2- = 0 2 Cr ions + 3 (2-) = 0 2 Cr ions - 6 = 0 2 Cr ions = +6 Cr ion = 3+ = Cr 3+ 2. Name the cation by the element name and add a Roman numeral in parenthesis to show its charge. Cr 3+ = chromium(iii) 3. Write the anion with an ide ending. chromium(iii) oxide = Cr 2 O 3 Copyright Houghton Mifflin Company. All rights reserved. 2 24

Learning Check Select the correct name for each. A. Fe 2 S 3 1) iron sulfide 2) iron(ii) sulfide 3) iron(iii) sulfide B. CuO 1) copper oxide 2) copper(i) oxide 3) copper(ii) oxide Copyright Houghton Mifflin Company. All rights reserved. 2 25

A polyatomic ion is a group of atoms. Binary Compounds with Polyatomic Ions has an overall ionic charge. Some examples of polyatomic ions are NH 4 + ammonium OH hydroxide NO 3 nitrate NO 2 nitrite CO 2 3 carbonate PO 3 4 phosphate HCO 3 hydrogen carbonate (bicarbonate) Copyright Houghton Mifflin Company. All rights reserved. 2 27

Some Names of Polyatomic Ions The names of common polyatomic anions end in ate. NO 3 nitrate PO 3 4 phosphate with one oxygen less end in ite. NO 2 nitrite PO 3 3 phosphite with hydrogen attached use the prefix hydrogen (or bi). HCO 3 hydrogen carbonate (bicarbonate) HSO 3 hydrogen sulfite (bisulfite) Copyright Houghton Mifflin Company. All rights reserved. 2 30

Naming Compounds with Polyatomic Ions The positive ion is named first followed by the name of the polyatomic ion. NaNO 3 K 2 SO 4 Fe(HCO 3 ) 3 sodium nitrate potassium sulfate iron(iii) bicarbonate or iron(iii) hydrogen carbonate (NH 4 ) 3 PO 3 ammonium phosphite Copyright Houghton Mifflin Company. All rights reserved. 2 33

Learning Check Match each formula with the correct name. A. MgS 1) magnesium sulfite MgSO 3 2) magnesium sulfate MgSO 4 3) magnesium sulfide B. Ca(ClO 3 ) 2 1) calcium chlorate CaCl 2 2) calcium chlorite Ca(ClO 2 ) 2 3) calcium chloride Copyright Houghton Mifflin Company. All rights reserved. 2 36

Solution Match each formula with the correct name: A. MgS 3) magnesium sulfide MgSO 3 1) magnesium sulfite MgSO 4 2) magnesium sulfate B. Ca(ClO 3 ) 2 1) calcium chlorate CaCl 2 3) calcium chloride Ca(ClO 2 ) 2 2) calcium chlorite Copyright Houghton Mifflin Company. All rights reserved. 2 37

Solution Name each of the following compounds: A. Mg(NO 3 ) 2 magnesium nitrate B. Cu(ClO 3 ) 2 copper(ii) chlorate C. PbO 2 lead(iv) oxide D. Fe 2 (SO 4 ) 3 iron(iii) sulfate E. Ba 3 (PO 3 ) 2 barium phosphite Copyright Houghton Mifflin Company. All rights reserved. 2 39

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 has the polyatomic ions in parentheses. Mg 2+ and 2NO 3 Mg(NO 3 ) 2 subscript 2 for charge balance Copyright Houghton Mifflin Company. All rights reserved. 2 40

Learning Check Select the correct formula for each. A. aluminum nitrate 1) AlNO 3 2) Al(NO) 3 3) Al(NO 3 ) 3 B. copper(ii) nitrate 1) CuNO 3 2) Cu(NO 3 ) 2 3) Cu 2 (NO 3 ) C. iron(iii) hydroxide 1) FeOH 2) Fe 3 OH 3) Fe(OH) 3 D. tin(iv) hydroxide 1) Sn(OH) 4 2) Sn(OH) 2 3) Sn 4 (OH) Copyright Houghton Mifflin Company. All rights reserved. 2 41

Solution Select the correct formula for each. A. aluminum nitrate 3) Al(NO 3 ) 3 B. copper(ii) nitrate 2) Cu(NO 3 ) 2 C. iron(iii) hydroxide 3) Fe(OH) 3 D. tin(iv) hydroxide 1) Sn(OH) 4 Copyright Houghton Mifflin Company. All rights reserved. 2 42

Learning Check Write the correct formula for each. A. potassium bromate B. calcium carbonate C. sodium phosphate D. iron(iii) oxide E. iron(ii) nitrite Copyright Houghton Mifflin Company. All rights reserved. 2 43

Solution Write the correct formula for each. A. potassium bromate KBrO 3 B. calcium carbonate CaCO 3 C. sodium phosphate Na 3 PO 4 D. iron(iii) oxide Fe 2 O 3 E. iron(ii) nitrite Fe(NO 2 ) 2 Copyright Houghton Mifflin Company. All rights reserved. 2 44

QUESTION Hypochlorous acid is related to the anion found in common household bleach. Which of the following is that common anion? 1. ClO 4 2. ClO 3 3. ClO 2 4. ClO Copyright Houghton Mifflin Company. All rights reserved. 2 49

QUESTION Which of the following provides the correct name for Ca(H 2 PO 4 ) 2? 1. Calcium dihydrogen phosphate 2. Calcium (II) hydrogen phosphate 3. Calcium di-dihydrogen phosphate 4. Calcium (II) dihydrogen phosphate Copyright Houghton Mifflin Company. All rights reserved. 2 50

Binary Covalent Compounds (Type III) Covalent bonds form when atoms share electrons to complete octets. between two nonmetal atoms. between nonmetal atoms from Groups 4A(14), 5A(15), 6A(16), and 7A(17). Copyright Houghton Mifflin Company. All rights reserved. 2 51

Naming Covalent Compounds To name covalent compounds STEP 1: Name the first nonmetal as an element. STEP 2: Name the second nonmetal with an ide ending. STEP 3: Use prefixes to indicate the number of atoms (subscript) of each element. Table 2.6 Copyright Houghton Mifflin Company. All rights reserved. 2 52

Naming Covalent Compounds What is the name of SO 3? 1. The first nonmetal is S sulfur. 2. The second nonmetal is O named oxide. 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. Copyright Houghton Mifflin Company. All rights reserved. 2 53

Naming Covalent Compounds Name P 4 S 3. 1. The first nonmetal P is phosphorus. 2. The second nonmetal S is sulfide. 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 Copyright Houghton Mifflin Company. All rights reserved. 2 54

Learning Check Select the correct name for each compound. A. SiCl 4 1) silicon chloride 2) tetrasilicon chloride 3) silicon tetrachloride B. P 2 O 5 1) phosphorus oxide 2) phosphorus pentoxide 3) diphosphorus pentoxide C. Cl 2 O 7 1) dichlorine heptoxide 2) dichlorine oxide 3) chlorine heptoxide Copyright Houghton Mifflin Company. All rights reserved. 2 56

Solution Select the correct name for each compound. A. SiCl 4 3) silicon tetrachloride B. P 2 O 5 3) diphosphorus pentoxide C. Cl 2 O 7 1) dichlorine heptoxide Copyright Houghton Mifflin Company. All rights reserved. 2 57

Solution Write the name of each covalent compound. CO CO 2 PCl 3 CCl 4 N 2 O carbon monoxide carbon dioxide phosphorus trichloride carbon tetrachloride dinitrogen monoxide Copyright Houghton Mifflin Company. All rights reserved. 2 59

Guide to Writing Formulas The prefixes in the name are used to write the formula. 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 Copyright Houghton Mifflin Company. All rights reserved. 2 60

Learning Check Write the correct formula for each of the following. A. phosphorus pentachloride B. dinitrogen trioxide C. sulfur hexafluoride Copyright Houghton Mifflin Company. All rights reserved. 2 61

Solution Write the correct formula for each of the following. A. phosphorus pentachloride 1 P penta = 5 Cl PCl 5 B. dinitrogen trioxide di = 2 N tri = 3 O N 2 O 3 C. sulfur hexafluoride 1 S hexa = 6 F SF 6 Copyright Houghton Mifflin Company. All rights reserved. 2 62

Learning Check Identify each compound as ionic or covalent and give its correct name. A. SO 3 B. BaCl 2 C. (NH 4 ) 3 PO 4 D. Cu 2 CO 3 E. N 2 O 4 Copyright Houghton Mifflin Company. All rights reserved. 2 63

Binary Acids Acids produce H + when dissolved in water. They are compounds that ionize in water. If the anion does not contain oxygen: HCl hydrogen chloride hydrochloric acid HF hydrogen fluoride hydrofluoric acid If the anion contain oxygen Anion ends in-ate, the suffix ic is added to the root name. Anion ends in ite, the suffix ous. Copyright Houghton Mifflin Company. All rights reserved. 2 65