Review Ch 2 Gupta Chapter 2: Naming, Atoms, Ions, Isotopes and Mass Spectroscopy

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1 Chapter 2: Naming, Atoms, Ions, Isotopes and Mass Spectroscopy Learning objective 1.3 The student is able to select and apply mathematical relationships to mass data in order to justify a claim regarding the identity and/or estimated purity of a substance. [See SP 2.2, 6.1; Essential knowledge1.a.2] Learning objective 1.12 The student is able to explain why a given set of data suggests, or does not suggest, the need to refine the atomic model from a classical shell model with the quantum mechanical model. [See SP 6.3; Essential knowledge 1.C.2] Learning objective 1.13 Given information about a particularmodel of the atom, the student is able to determine if the model is consistent with specified evidence. [See SP 5.3; Essential knowledge 1.D.1] Learning objective 1.14 The student is able to use data from mass spectrometry to identify the elements and the masses of individual atoms of a specific element. [See SP 1.4, 1.5; Essential knowledge 1.D.2] Learning objective 2.1 Students can predict properties of substances based on their chemical formulas, and provide explanations of their properties based on particle views. [See SP 6.4, 7.1; Essential knowledge components of 2.A 2.D] NOTE: The grayed out content is phased out! Understand the keywords given below. Be sure to define each key word with a simple oneline definition. Atom, Cathode Ray Tube, J. J. Thompson, Electron, Charge to mass ratio of electron, Millikan s Oil Drop experiment, Nuclear Atom, Rutherford, Gold Foil Experiment, Subatomic Particles, Cation, Anion, Isotopes, Atomic Number, Mass Number, Naming of Compounds, Ionic Compounds, Variable Valency Cations, Molecular Compounds, Prefix Way of Naming, Stock Way of Naming, Acids, Oxyacids, Complex Compounds, Naming of Complex Compounds Descriptive Colors (Only memorize the highlighted ones!) Flame Test Colors Li + Na + K + Ca 2+ Sr 2+ Ba 2+ Cu 2+ Deep red (crimson) Yellow Violet Orangered Red Green Bluegreen Aqueous Ion Colors Cu 1+ Cu 2+ Green Blue Fe Yellow to redorange (depending on anion and charge of Fe); in rare cases, can form complex ion with a deep blue color Fe 2+ yellowgreen (depending on the anion) Fe 3+ orangered (depending on the anion) Co 2+ Pink Cr 3+ Violet (Cr(NO 3 ) 3 to Green (CrCl 3 ) Ni 2+ Green Mn 2+ Pink Pb 3+ bluegreen (Pb 2+ and Pb 4+ are colorless) V 2+ violet

2 V 3+ Zn 2+ MnO 4 CrO Cr 2 O 7 2+ Cu(NH 3 ) 4 FeSCN 2+ 2 CoCl 4 3+ Ti(H 2 O) 6 bluegreen Colorless/milky Purple (Mn w/ +7 oxidation state is purple) Yellow Orange Dark Blue; produced when ammonia is added to Cu 2+ solutions Redbrown, Winered to dark orange Blue (Co 2+ with HCl will form a CoCl 2 4 complex that is blue) Purple Al, K, Li, Mg, Na, Ca, Ba, Sr, Zn are colorless aqueous ions and most of their solid salts are white. Transition element ions with partially filled d orbitals tend to release colored light. Assorted Compounds F 2 Paleyellow gas Cl 2 Greenyellow gas Br 2 Redbrown liquid I 2 Darkviolet vapor & dark metallic looking solid S 8 Yellow, odorous solid NO Colorless gas; associated with reactions between metals and dilute HNO 3 NO 2 Brown gas; associated with reactions between metals and concentrated HNO 3 PbI 2 Bright yellow precipitate Metallic sulfides Sulfides of transition metals tend to be black AgX (Silver Halide) White AgNO 3 White, turns black in sunlight CuO Green HgO Dark Red Fe 2 O 3 Reddish brown (rust) Metallic oxides Oxides of colored transition metal ions tend to be colored AcidBase Indicators Phenolphthalein Red Litmus (paper) Blue Litmus (paper) Colorless (ph<7) to Pink (ph>8 ; when OH is present) Turns purple in alkaline solution Turns pink in acidic solution Naming Compounds Review for AP Chemistry Before naming a compound, it is important to know why type of compound it is. There are ionic compounds, molecular compounds, and acids. Ionic Compound can be identified by the presence of a metal in it. (generally solids) Molecular compound is made up of all non metals. (generally liquids and gases) Acids begin with H (generally present as aq solutions or gases) To name an ionic compound: Name metal first, followed by a roman numeral specifying its charge (ONLY if variable valency), then name the anion (monoatomic ending in ide, and polyatomic named as such). Ex. MgO (Magnesium Oxide), Na 2 S (Sodium Sulfide), Fe 2 O 3 (Iron (III) Oxide), (NH 4 ) 2 SO 4 (Ammonium Sulfate) To write the formula of an ionic compound:

3 Use crisscross method (bring valency of one element down as a subscript next to the other element). Write the formulas of the following: Sodium Sulfide (Na 2 S), Potassium Nitrate (KNO 3 ), Ferrous Sulfate Fe (SO 4 ), Ammonium Chloride (NH 4 Cl) To name a molecular compound: Write name of the first element followed by its oxidation state in parenthesis or you can use older prefix way. Example: CO 2 can be named as Carbon (IV) Oxide or Carbon dioxide To name an acid without oxygen: Starts with Hydrofollowed by the name of anion ending in ic Acid. Ex. HCl! Hydrochloric acid To name an acid with Oxygen (Oxyacids): Anion ending decides the name of the acid. If anion ends in ate, then acid is ic acid, if anion ends in its, then acid is ous acid. Ex. HClO 4! Perchloric Acid (anion perchlorate) HClO 3! Chloric Acid (anion Chlorate) To name a complex ion: Name cation first followed by anion. Within a complex, transition metal is named first with its charge listed within parenthesis, followed by ligands and then anion. If complex is anion, then its name ends in ate. Common Cations with Variable Valency (Must Memorize) Cuprous, Cupric Copper Cu Cu + Cu 2+ Cobaltous, Cobatic Cobalt Co Co 2+ Co 3+ Chromous, Chromic Chromium Cr Cr 2+ Cr 3+ Ferrous, Ferric Iron Fe Fe 2+ Fe 3+ Plumbous, Plumbic Lead Pb Pb 2+ Pb 4+ Mercurous, Mercuric Mercury Hg Hg 2+ 2 Hg 2+ Stannous, Stannic Tin Sn Sn 2+ Sn 4+ Common Ions (Must Memorize) Ammonium NH 4 + Chlorate ClO 3 Thiosulfate S 2 O 3 2 Nitrate NO 3 Perchlorate ClO 4 Thiocynate SCN Phosphate 3 PO 4 Chlorite ClO 2 Peroxide 2 O 2 Hydroxide OH Hypochlorite ClO Sulfite 2 SO 3 Sulfate 2 SO 4 Permanganate MnO 4 Nitrite NO 2 Carbonate 2 CO 3 Acetate C 2 H 3 O 2 Phosphite 3 PO 3 CH 3 COO Chromate 2 CrO 4 Bicarbonate (hydrogen HCO 3 Bisulfate (hydrogen HSO 4 Dichromate Cr 2 O 7 2 carbonate) sulfate) Cyanide CN Oxide O 2

4 Now some practice: 1. Mg 3 P 2 2. NaF 3. Sr(MnO 4 ) 2 4. Cr 3 (PO 4 ) 2 5. Al 2 Se 3 6. FeCl 3 7. HNO 3 8. Ferrous Sulfate 9. Ammonium Carbonate 10. Copper(II) Chloride 11. Dinitrogen Monoxide 12. Sulfuric Acid Answers: 1. Magnesium Phosphide 2. Sodium Fluoride 3. Strontium Permanganate 4. Chromium (II) Phosphate 5. Aluminum Selenide 6. Iron(II) Chloride, Ferric Chloride 7. Nitric Acid 8. FeSO 4 9. (NH 4 ) 2 CO CuCl N 2 O 12. H 2 SO 4 Problem Set Level 1: 6, 8, 12, 32, 35, 40, 43, 45, 30, 31, 41, 42, 44, 46, 64 Level 2 WS 1. Complete the table below using the clues provided. Symbol 39 K 33 S 2 Protons 26 Neutrons Electrons 24 Atomic no. 87 Mass no. Net charge Provide the name of chemical formula (as needed) of the following compounds. a. Ba(OH) 2 *(H 2 O) 8 b. N 2 c. HClO d. K 2 HPO 4 e. AgH f. CsO 2

5 g. Pb(OH) 2 h. NH 4 NO 3 i. ZnO j. Hydrobromic acid k. Bromic acid l. Perchloric acid m. Chloric acid n. Hydrochloric acid o. Aluminum nitrite p. Aluminum nitride q. Potassium sulfite r. Potassium bisulfite s. Periodic acid Answers: 1. Complete the table below using the clues provided. Symbol 39 K 56 Fe S Fr + Protons Neutrons Electrons Atomic no Mass no Net charge Provide the name of chemical formula (as needed) of the following compounds. a. Ba(OH) 2 *(H 2 O) 8 barium hydroxide octahydrate b. N 2 nitrogen (molecular) c. HClO hypochlorous acid d. K 2 HPO 4 potassium hydrogen phosphate e. AgH silver hydride f. CsO 2 cesium oxide g. Pb(OH) 2 lead (II) or plumbous hydroxide h. NH 4 NO 3 ammonium nitrate i. ZnO zinc oxide j. Hydrobromic acid HBr k. Bromic acid HBrO 3 l. Perchloric acid HClO 4 m. Chloric acid HClO 3 n. Hydrochloric acid HCl o. Aluminum nitrite Al(NO 2 ) 3 p. Aluminum nitride AlN q. Potassium sulfite K 2 SO 3 r. Potassium bisulfite (or potassium hydrogen sulfite) KHSO 3 s. Periodic acid HIO 4

6 Mass Spectroscopy Problems DRAWING MASS SPECTRA 1. Write the relative value above each peak. The y axis is the RELATIVE abundance, not the. Calculate the and average atomic mass of the following elements. Identify the element. A. mass # 6 mass # 7 Atomic mass Element identity Work: Relative % Abundance Mass/e Relative % B. mass # 102 mass # 104 mass # 105 mass # 106 mass # 108 mass # 110 Atomic mass Element identity Work: Mass/e Relative % Sketch mass spectra for the following set of isotopes. The most abundant must 42.9 be set to 100 as a relative abundance. Label both axis and the relative % Relative % Abundance

7 abundance above the corresponding line on the spectrum. Calculate the atomic mass and put it in the table. A. Rubidium Isotope Mass number % abundance 85 Rb Rb Atomic mass: B. Germanium Isotope Mass % Isotope Mass % number abundance number abundance 70 Ge Ge Ge Ge Ge Atomic Mass: Answers to Mass Spectroscopy 3. Write the relative value above each peak. The y axis is the RELATIVE abundance, not the. Calculate the and average atomic mass of the following elements. Identify the element. A. mass # 6 mass # % Atomic mass 6.93 amu 92.6% Element identity Li Work: Relative % Abundance Mass/e Relative %

8 B. mass # 102 mass # 104 mass # 105 mass # % mass # % 11.1% mass 11.7% # % Atomic mass amu 27.3% Element identity Pd Work: Relative % Abundance 4. Sketch mass spectra for the following set of isotopes. The most abundant must be set to 100 as a relative abundance. Label both axis and the relative % abundance above the corresponding line on the spectrum. Calculate the atomic mass and put it in the table. A. Rubidium Isotope Mass number % abundance 85 Rb Rb Atomic mass: amu (Rb) Mass/e Relative %

9 , , B. Germanium Isotope Mass % Isotope Mass % number abundance number abundance 70 Ge Ge Ge Ge Ge Atomic Mass: , , , , , Real Life Mass Spectroscopy Problems 1. Mass Spectroscopy can be used to detect steroid in athlete s urine sample. Look at the graphs below and tell us if the tested urine sample contains steroids? Explain your reasoning.

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