3 Atoms and Ions are electrically neutral. Same number of p+ and e-- atoms with a charge (+ or -)Made by gaining or losingOnly electrons can move
4 F1- O2- An Anion is… A negative ion = electrons. Nonmetals gain electrons.Charge is written as a superscript on the right.F1-Has gained electron (-ide is new ending = )O2-Gained electrons ( )
5 K1+ Ca2+ A Cation is… A positive ion = electrons. lose electrons Has lost electron (no name change for positive ions)More protons than electronsCa2+Has lost electrons
6 Predicting Ionic Charges Group 1A:Lose electron to form ionsH1+Li1+Na1+K1+Rb1+
7 Predicting Ionic Charges Group 2A:Loses electrons to form ionsBe2+Mg2+Ca2+Sr2+Ba2+
8 Predicting Ionic Charges Loses electrons to formionsGroup 3A:B3+Al3+Ga3+
9 Predicting Ionic Charges ! Group 4A elements rarely form ions (they tend to share)Group 4A: Do they lose 4 electrons or gain 4 electrons?
10 Predicting Ionic Charges NitrideGains _electrons to formionsGroup 5A:P3-PhosphideAs3-Arsenide
11 Predicting Ionic Charges OxideGains electrons to form ionsGroup 6A:S2-SulfideSe2-Selenide
12 Predicting Ionic Charges Gains _ electron to form ionsGroup 7A:F1-FluorideBr1-BromideCl1-ChlorideI1-Iodide
13 Predicting Ionic Charges Group 8A: Stable noble gases form ions!
14 Predicting Ionic Charges Group B elements: Many transition elementshave possible charge.Use of Roman numerals to show chargesIron (II) =Iron (III) =Show roman numerals up to 5.
15 Naming Cationssystem – use roman numerals in parenthesis to indicate the charge value2. Classical method – uses root word with suffixes (-ous, -ic)Does not give true value
16 Naming cationsIf the charge is always the (like in the Group A metals) just write the of the metal.Calcium = 𝐶𝑎 +2metals can have more than one type of charge.Indicate charge as roman numeral in after the name of the metal (Table 9.2, p.255)Iron (IV) =
17 Predicting Ionic Charges Some elements alsohave more than one possible charge.Tin (II) =Lead ( ) = Pb2+Tin (IV) =Lead ( ) = Pb 4+
18 Predicting Ionic Charges Group elements:Some transition elementshave only one possible oxidation state, such as these three:**Do not use roman numerals for theseSilver =Zinc =Cadmium =
19 Practice by naming these: Ca2+Al3+Fe3+Fe2+Pb2+Li+
20 Write symbols for these: Potassium ionMagnesium ionCopper (II) ionChromium (IV) ionBarium ionMercury (II) ion
21 Anions are the same charge Change the ending to _ Naming AnionsAnions are the same chargeChange the ending to _F1- a Fluorine atom will become a ion.
23 Write symbols for these: Sulfide ionIodide ionPhosphide ionStrontium ion
24 Polyatomic ions are…Groups of atoms that together, have an charge, and one name.Usually end in – or _Acetate: C2H3O2-Nitr : NO3-Nitr : NO2-Permanganate: MnO4-Hydroxide: OH- and Cyanide: CN-?
25 Know Table 9.3 on page 257 Sulf : SO42- Phosph : PO43- Sulf : SO32- Carbonate: CO32-Chromate: CrO42-Dichromate: Cr2O72-Phosph : PO43-Phosph : PO33-Ammonium: NH41+(One of the few positive polyatomic ions)
26 H + Polyatomic ion =….If the polyatomic ion begins with H, then put “hydrogen” in front of the polyatomic ion: H CO32- → HCO31- hydrogen + carbonate → hydrogen carbonate ionHSO3HPO4HCO3
27 Helpful Hints on Oxy-Anions 1. _________: smaller # of oxygen2. _________: larger # of oxygenEx.NO3- ____________________________NO2- ____________________________SO42- ____________________________SO32- ____________________________
28 A Guide to Determine Whether the –ate Formula is –XO3 or –XO4: 123456131415161718Transition MetalsBCNSiPSClAsSeBrI
29 Section 9.2 Naming and Writing Formulas for Ionic Compounds
30 Writing Ionic Compound Formulas Example: Iron (III) chloride1. Write the cation and anion with CHARGES!2. Balance charges using the criss-cross method with subscripts, if necessary. Use parentheses if you need more than one of a polyatomic ion to balance subscripts.
31 Writing Ionic Compound Formulas Example: Aluminum sulfide1. Write the cation and anion with CHARGES!2. Balance charges using the criss-cross method with subscripts, if necessary. Use parentheses if you need more than one of a polyatomic ion to balance subscripts.
32 Writing Ionic Compound Formulas Example: Zinc hydroxide1. Write the cation and anion with CHARGES!2. Balance charges using the criss-cross method with subscripts, if necessary. Use parentheses if you need more than one of a polyatomic ion to balance subscripts.
33 Writing Ionic Compound Formulas Example: Magnesium carbonate (note the 2 word name)1. Write the formulas for the cation and anion, including CHARGES!Mg2+CO32-2. Check to see if charges are balanced.They are balanced!
34 Writing Ionic Compound Formulas Example: Barium nitrate (note the 2 word name)1. Write the cation and anion with CHARGES!2. Balance charges using the criss-cross method with subscripts, if necessary. Use parentheses if you need more than one of a polyatomic ion to balance subscripts.
35 Writing Ionic Compound Formulas Example: Ammonium sulfate1. Write the cation and anion with CHARGES!2. Balance charges using the criss-cross method with subscripts, if necessary. Use parentheses if you need more than one of a polyatomic ion to balance subscripts.
36 Writing Ionic Compound Formulas Example: Aluminum phosphate1. Write the formulas for the cation and anion, including CHARGES!Al3+PO43-They ARE balanced!2. Check to see if charges are balanced.
37 Naming Ionic Compounds 1. Cation , then anion2. Monatomic cation = name of the elementCa2+ = ion3. Monatomic anion = root + -ideCl- =CaCl2 =
38 Naming Ionic Compounds (Metals with multiple oxidation states)If the metal can have more than one charge ( ), use a Roman numeral in their name:PbCl2 use the to find the charge on the cation (chloride is always 1-)is the lead ( ) cationPbCl2 = lead ( ) chloride
39 Things to look for:If cations have ( ), the number in parenthesis is their .If anions end in –ide, they are probably off the periodic table ( )If anion ends in -ate or –ite, then it is
40 Practice by writing the formula or name as required… Iron (II) PhosphateStannous FluoridePotassium SulfideAmmonium ChromateMgSO4FeCl3
41 Section 9.3 Naming and Writing Formulas for Molecular Compounds
42 Molecular compounds are… Made of onlySmallest part is aCan’t use charges to figure out how many of each atom (there are no charges present / they share electrons)
43 Molecular compounds are easier! compounds use to determine how many of each.Figure out charges and criss-cross numbers.Molecular compounds: the name tells you the number of atoms.Uses to tell you the exact number of each element present!
45 Prefixes Prefix + name -ide To write the name, include:One exception is we don’t write if there is only of the element.Normally, we do not have double vowels when writing names (oa oo)Prefix + name -ide
46 Practice by naming these: N2ONO2Cl2O7CBr4CO2BaCl2
48 Section 9.4 Naming and Writing Formulas for Acids and Bases
49 Acids are…Compounds that give off ions (H+) when dissolved in water (the Arrhenius definition)Formula starts with .Always be some Hydrogen next to an .determines the name.
50 Rules for Naming acids: Name it as a normal compound first If the anion attached to hydrogen ends in -ide, put the prefix and change -ide to - acidIn other words, if it’s just Hydrogen and one other nonmetalHCl =H2S =acidacid
51 Naming AcidsIf the anion has oxygen in it, then it ends in -ate or -iteChange -ate to -ic acid (use no prefix)Example: HNO Hydrogen + nitrate =Change -ite to -ous acid (use no prefix)Example: HNO Hydrogen + nitrite =
52 Naming Acids ____-ide ____-ate ____-ite hydro-___-ic acid Normal ending____-ide____-ate____-iteAcid name is…hydro-___-ic acid_____-ic acid_____-ous acid
53 Practice by naming these: HFH3PH2SO4H2SO3HCNH3PO4
54 Writing Acid Formulas – in reverse! Hydrogen will be listed firstThe name will tell you theBe sure the charges cancel out.Starts with hydro?No hydro?Anion is , ends in –ide-ate anion comes from – ending-ite anion comes from – ending
56 Names and Formulas for Bases Base - an ionic compound that produces ions ( ) when dissolved in water (the Arrhenius definition)Named the same way as other ionic compounds:Name of cation ( ) followed by name of anion (which will be ).
57 Names and Formulas for Bases NaOH =Ca(OH)2 =To write the formula:Write symbol for metal cationFollowed by hydroxide ion (OH1-)Use criss-cross method to balance the charges.
58 Practice by writing the formula for the following: Magnesium hydroxideIron (III) hydroxideZinc hydroxide
59 Section 9.5 The Laws Governing Formulas and Names
60 Some Laws:Law of Proportions- in a sample of a chemical compound, the of the are always in the proportions.In every molecule of H2O (water), the mass ratio of H:O is 1:8
61 Some Laws:Law of Proportions- Whenever two elements form than one compound, the masses of one element that combine with the mass of the other element are in the ratio of smallH2O (water) and H2O2 (hydrogen peroxide)2: :22g:16g g:32g
62 https://www.youtube.com/watch?v=0OOcpiTiXzMLaw of Definite Proportions - Law of Multiple Proportionsby Brightstorm
63 Summary of Naming and Formula Writing For naming, follow the flowchart- Figure 9.20, page 277For writing formulas, follow the flowchart from Figure 9.22, page 278
64 Helpful to remember...1. In ionic compounds, the net charge is _ (criss-cross method)2. Put -ide at the end of monatomic3. An -ite or -ate ending means there is a ion that has4. Prefixes generally mean ; they show the number of each atom
65 Helpful to remember...5. A Roman numeral after the name of a cation is the of the cation