Chamras Chemistry 110 Lecture Exam 2 Materials Chapter 5 A Brief Detour on the Development of the Periodic Table of Elements In Ancient Chinese Philosophy: In Greek Philosophy: Dmitri Mendeleev s Original Periodic Table: (Based on Average Atomic Mass) 1
A brief review on the Periodic Table: Chemical Nomenclature The Periodic Table: Lists all the elements that are so far known to us. Most of the elements are naturally occurring but some are human-made. Metals and non-metals are separated by the zigzag line starting at B(boron), and ending At(astatine). With the exception of aluminum (Al), all the elements touching the metal-non-metal separation line are called metalloids or semi-metals. Metals lose electrons (become cations) and non-metals gain electrons (become anions) when ionized. Metals of Groups 1, 2, and 13 assume charges of +1, +2, and +3 respectively, when ionized. Non-metals of groups 15, 16, and 17, assume charges of 3, 2, and 1 respectively, when ionized. When formulating an ionic compound, the Principle of Neutrality applies. Compound: Definition: Chemical Bonding: Ionic Bonding: Covalent Bonding: Types of Compounds: Ionic Compounds: Molecular Compounds: 2
Review Exercise: Determine the formulas for ionic compounds made with the following ions: a) Al 3+ and O 2 : b) Ca 2+ and P 3 : c) Li + and Cl : d) Fe 2+ and N 3 : Charges of Ions: H Li Be Simple Cations with Fixed Charges Na Mg Al K Ca Zn Rb Sr Ag Cd Cs Ba Fr Ra Simple Cations with Variable Charges Cr Mn Fe Co Ni Cu As Sn Au Hg Pb Sb Bi 3
H Simple Anions N O F P S Cl Br I Chemical Nomenclature: IUPAC: Types of Naming: a) Ionic Compounds b) Binary Molecular Compounds c) Acids d) Bases How to tell these types apart by just looking at the formula? Formula Indicator Example Ionic------------ Molecular------ Acid------------ Base------------ 4
Naming Ions: 1. Cations with fixed charge: {Name of Neutral Element + ion } 2. Cations with variable charge: Two methods: a) {Name of Neutral Element + Charge + ion } b) {Latin Rootname of Neutral Element + ous for lower charge, and ic for higher charge + ion } Simple Anions: {Rootname of element + ide } Naming Ionic Compounds: Element Name Lower Name Higher Name Charge Ion Charge Ion Cr chromium Cr 2+ chromous Cr 3+ chromic Mn manganese Mn 2+ manganous Mn 3+ manganic Fe ferrum Fe 2+ ferrous Fe 3+ ferric Co cobalt Co 2+ cobaltous Co 3+ cobaltic Ni nickel Ni 2+ nickelous Ni 3+ nickelic Cu cuprum Cu + cuprous Cu 2+ cupric Au aurum Au + aurous Au 3+ auric Hg mercury Hg 2+ 2 [Hg + ] mercurous Hg 2+ mercuric (hydrargyrum) Sn Stannum Sn 2+ stannous Sn 4+ stannic Pb Plumbum Pb 2+ plumbous Pb 4+ plumbic As arsenicum As 3+ arsenous As 5+ arsenic Sb antimonium Sb 3+ antimonious Sb 5+ antimonic (stibium) Bi bisemutum Bi 3+ bisemutous Bi 5+ bisemutic 5
1. Naming ionic compounds made of simple (monatomic) cations and anions: { Remember: Formula for ionic compounds cation-anion sequence} The name follows the same sequence as the formula does: a) If the cation is fixed-charge: {Name of the cation + Name of the anion} b) If the cation is a variable-charge, there are two methods: 1) { Name of element + (Charge of cation indicated in Roman numeral form) + Name of the anion} 2) { Latin name of cation + ous or ic + Name of the anion} 6
Practice problems for writing names and formulas: Complete the following Table: Chemical Formula IUPAC Name Chem. Formula IUPAC Name Na 3 P potassium chloride CaO FeN (two ways) aurous nitride barium fluoride manganic oxide Fe 3 N 2 (two ways) HgCl 2 Al 2 S 3 MgBr 2 SnO 2 chromium (III) phosphide iron(ii) iodide cuprous nitride silver oxide aluminum bromide copper(i) phosphide 2. Naming ionic compounds made of simple cations and polyatomic anions: Polyatomic Ions: Ions made of more than one atom. 7
List of Polyatomic Ions The Only Polyatomic Cation: + 2+ NH 4 ammonium ion Hg 2 mercury(i) or mercurous ion Polyatomic anions: Charge 1 Charge 2 Charge 3 H 2 PO 4 dihydrogen phosphate HPO 4 2 monohydrogen phosphate PO 4 3 phosphate H 2 PO 3 dihydrogen phosphite HPO3 2 monohydrogen phosphite PO 3 3 phosphite HCO 3 HSO 4 HSO 3 NO 3 NO 2 bicarbonate 2 CO 3 (hydrogen carbonate) bisulfate 2 SO 4 (hydrogen sulfate) bisulfite 2 SO 3 (hydrogen sulfite) nitrate 2 O 2 nitrite 2 CrO 4 carbonate sulfate sulfite peroxide chromate C 2 H 3 O 2 acetate Cr 2 O 7 2 BrO 4 perbromate C 2 O 4 2 dichromate oxalate BrO 3 BrO 2 BrO CN OCN SCN MnO 4 OH bromate bromite hypobromite cyanide cyanate thiocyanate permanganate hydroxide 8
Practice problems for writing names and formulas: Complete the following table: Chemical Formula IUPAC Name Chem. Formula IUPAC Name Na 3 PO 4 potassium chlorate CaO 2 Fe(NO 2 ) 2 (two ways) aurous nitrite barium perbromate manganic peroxide Fe(NO 3 ) 3 (two ways) mercury (I) phosphite iron(ii) hypoiodite Hg 2 Cl 2 Al 2 (SO 4 ) 3 Mg(BrO 2 ) 2 Sn(CO 3 ) 2 cuprous sulfate silver oxalate aluminum acetate copper(ii) permanganate Naming Binary Molecular Compounds: Remember: Molecular compounds are made of non-metals. Rules: 1. Naming takes the form: {(# prefix + name of the first element) + (# prefix + name of the second ion)} 9
2. The number of each type of element must be specified using Latin prefixes (see table below). 3. The only exception is the first element. If there is only one of the first written element in the formula, then the number should not be specified. Latin Number Prefixes: Prefix Meaning Prefix Meaning mono- one hexa- six di- two hepta- seven tri- three octa- eight tetra- four nona- nine penta- five deca- ten Practice problems for naming binary molecular compounds: Complete the following table: IUPAC Name dichloro pentaphosphide dinitrogen monoxide CO 2 N 2 O 4 NO Chemical Formula Naming Acids: Definition of Acids: 10
There are two methods of naming the acids: a) Binary Acids: { hydro + rootname of the second element + ic acid } HBr(aq) b) Oxy-Acids: { rootname of the non-oxygen, non-hydrogen element + ic acid (with higher # of oxygens OR ous acid with lower # of oxygens} Examples: HBrO 3 (aq) HBrO 2 (aq) ***If the formula of the acid is displayed without the (aq) solution indicator, then name it as an ionic compound (name the hydrogen as a cation) uniformly, regardless of the type being binary or oxy-acid. Examples: HBr HBrO 3 HBrO 2 Practice problems for naming acids: Complete the following table: IUPAC Name hydrobromic acid hydrogen nitrite hypoiodous acid hydrogen sulfide HClO 4 (aq) HClO 3 HNO 2 (aq) H 3 PO 4 Chemical Formula 11
Naming Bases: Definition for bases: Bases should be named as ionic compounds. Examples: NaOH KOH LiOH Ca(OH) 2 Ba(OH) 2 NH 4 OH Nomenclature Exercise: Complete the following naming tables: Name Formula Name Formula barium nitrate H 2 SO 4 (aq) dichloro pentoxide AlI 3 mercurous peroxide Hg 3 (PO 4 ) 2 bromic acid AuOH ammonium sulfite Ag 2 O 2 hydrogen perchlorate HBrO 2 sulfur trioxide Mn(NO 2 ) 3 ferric bicarbonate K 2 O hydroiodic acid NO periodic acid HCl Naming Hydrates: Hydrate (Definition): Naming: 12
Nomenclature Chart: 13
What Is A Chemical Reaction? Chapter 6 Chemical Reactions Evidences for Chemical Reactions: 1. Formation of solid 2. Formation of Gas 3. Evolution or Absorption of Heat (Thermal Energy) 4. Color Change Chemical Equations: A Short Hand Method to Describe Chemical Reactions Solid sodium metal reacts with water and forms aqueous sodium hydroxide and hydrogen gas. Writing Chemical Equations: Reactant Side Product Side Reaction Arrow States Relative Amounts: Law of Conservation of Mass 14
Balancing Chemical Equations 15
Chapter 7 Solution: Types of Chemical Reactions Components of Solution: Examples of Solutions: SOLVENT SOLUTE Example Solubility: Rule of Thumb on Solubility: 16
Dissolution Process in Water: a) For SOLUBLE Ionic Compounds: b) For POLAR Molecular Compounds: c) For Strong Acids & Bases: d) For Weak Acids & Bases: ***Dissociation: 17
1. Precipitation Reactions: CaCl 2 (aq) + AgNO 3 (aq) Types of Chemical Reactions What happens at the Molecular Level? When is there a NO REACTION case if any? How to Predict the Solubility Behavior of a Product? Use SOLUBILITY RULES ***Solubility Rules for Ionic Compounds: Behavior Compounds Containing the Ions of Exception(s) Soluble + Group 1 metals & NH 4 None Soluble - NO 3 None Soluble Cl -, Br -, I - Ag +, Hg 2+ 2, Pb 2+ Soluble 2- SO 4 Ba 2+, Pb 2+, Ca 2+ Insoluble S 2-, CO 2-3- 3, PO 4 + Group 1 metals & NH 4 Insoluble OH - Group 1 metals & NH + 4, Ca +, Ba 2+, Sr 2+ 18
Label the following ionic compounds as S (soluble) or I (insoluble). Na 3 PO 4 : AgBr: HgI 2 : PbCl 4 : Hg 2 Cl 2 : Li 2 S: BaCO 3 : Ca(OH) 2 : Fe(OH) 3 : 3 Ways to Write Chemical Equations: 1. Complete Molecular Equation: 2. Complete Ionic Equation: 3. Net Ionic Equation: 19
2. Neutralization Reactions: (AKA: Acid- Base reactions) MUST KNOW: ACID + BASE Acid: Base: Strength of Acids & Bases: List of Strong Acids: HCl(aq) HBr(aq) HI(aq) H 2 SO 4 (aq) HNO 3 (aq) HClO 4 (aq) List of Strong Bases: LiOH NaOH KOH RbOH CsOH Ca(OH) 2 Sr(OH) 2 Ba(OH) 2 Weak Acids: Weak Base: 20
How about a hydroxide that is not water-soluble? Exercise: a) Write the complete balanced molecular equation for the reaction of a solution of sulfuric acid and a solution of potassium hydroxide: b) Generate the complete ionic equation from part a above: c) Generate the net ionic equation from part b above: MUST KNOW: The net ionic equation for the reaction of a strong acid with a strong base: 3. a) Reactions of Metals with Non-metals: (AKA: Oxidation-Reduction) 21
Oxidation: Reduction: Oxidation Number: b) Reactions of Oxygen with Non-metals: c) Combustion Reactions: Combustion: Organic Compounds: 22
Exercise: Complete and balance the equation for the combustion reaction of pentane (Molecular Formula: C 5 H 12 ). Other Ways to See and Classify Chemical Reactions: Combination: Decomposition: Double Displacement: Single Replacement: Combustion: 23