Compounds Electron Shell. Covalent Bonds
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeLearning Goal Write the symbols for the simple ions of therepresentative elements.6.1 Ions: Transfer of ElectronsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeChapter 6Ionic and MolecularCompounds 2016 Pearson Education, Inc. 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc. Covalent bonds occur when nonmetal atoms shareelectrons to attain a noble gas arrangement. Ionic bonds occur when valence electrons of a metalatom are transferred to the atom of a nonmetal.Chemical bonds are formed when atoms lose, gain, orshare valence electrons to completely fill their outermostelectron shell.Ionic and Covalent BondsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 6.1 – Ions: Transfer of Electrons 6.2 – Writing Formulas for Ionic Compounds 6.3 – Naming and Writing Ionic Formulas 6.4 – Polyatomic Ions 6.5 – Molecular Compounds: Sharing Electrons 6.6 – Lewis Structures for Molecules and Polyatomic Ions 6.7 – Electronegativity and Bond Polarity 6.8 – Shapes and Polarity of Molecules 6.9 – Attractive Forces in CompoundsCh. 6 – Ionic and MolecularCompounds
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeWhen sodium atoms in Group1 are neutral, they have 11electrons and 11 protons. They lose one electron tohave the same number ofvalence electrons as neonand a filled energy level. They will form an ion with10 electrons, 11 protons,and an ionic charge of 1 :Na .Positive Ions: Loss of ElectronsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeIonic and Covalent Bonds 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeWhen magnesium atoms inGroup 2 are neutral, they have12 electrons and 12 protons. They will lose 2 electrons tohave the same number ofvalence electrons as neonand a filled energy level. They form an ion with 10electrons, 12 protons, withan ionic charge of 2 : Mg2 .Positive Ions: Loss of ElectronsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.In ionic bonding, ions form when atoms gain or losetheir valence electrons to form a stable electronconfiguration.Metals: have low ionization energies. readily lose one or more of their valence electronsto form ions with a positive charge. lose electrons until they have the same number ofvalence electrons as the nearest noble gas, usuallyeight valence electrons.Positive Ions: Metals Lose Electrons
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeFormulas, Names of Common IonsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.Nonmetals Have high ionization energies readily gain one or more valence electrons to form ionswith a negative charge. gain electrons until they have the same number of valenceelectrons as the nearest noble gas, usually eight valenceelectrons.Negative Ions: Nonmetals Gain Electrons 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.We can use the group numbers in the periodic table to determine thecharges for the ions.Ionic Charges, Group NumbersGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeWhen chlorine atoms inGroup 17 are neutral, theyhave17 electrons and 17protons. They will gain oneelectron to have thesame number of valenceelectrons as argon. They form an ion with 18electrons, 17 protons,and a charge of 1 : Cl .Negative Ions: Gain of Electrons
Principal cationoutside the cellCation outside the Major cation in bones,cell; found in bones needed for musclecontractionsK Ca2 2016 Pearson Education, Inc.Chlorophyll, nuts,grainsMilk, yogurt,cheese, greens,spinachBananas, potatoes,orange juice, milkSalt, cheese,picklesSourceGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.Consider the elements calcium and chlorine.A. Identify each as a metal or a nonmetal.B. State the number of valence electronsfor each.C. State the number of electrons that must be lost or gained for each to acquirean octet.D. Write the symbol, including its ionic charge, and name of each resulting ion.Study CheckGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeMg2 Cation outside the Essential for certaincell; found in bones enzymes, muscles, andnerve controlRegulation of body fluidsand cellular functionsRegulation and control ofbody fluidsPrincipal cationoutside the cellNa FunctionOccurrenceIonIons are important in regulating body functions.Chemistry Link to Health: Important Ions in theBodyGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 6.1 – Ions: Transfer of Electrons 6.2 – Writing Formulas for Ionic Compounds 6.3 – Naming and Writing Ionic Formulas 6.4 – Polyatomic Ions 6.5 – Molecular Compounds: Sharing Electrons 6.6 – Lewis Structures for Molecules and Polyatomic Ions 6.7 – Electronegativity and Bond Polarity 6.8 – Shapes and Polarity of Molecules 6.9 – Attractive Forces in CompoundsCh. 6 – Ionic and MolecularCompoundsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.Write the formula and symbol of an ion with16 protons and 18 electrons.Study Check
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeSodium chloride is morecommonly known as tablesalt. The magnification ofNaCl crystals shows thearrangement of Na andCl ions in an NaCl crystal.NaCl, An Ionic CompoundGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeLearning Goal Using charge balance, write the correct formula foran ionic compound.6.2 Writing Formulas forIonic Compounds 2016 Pearson Education, Inc. 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.In a chemical formula, the symbols and subscripts are written in the lowest whole-numberratio of the atoms or ions. the sum of ion charges equals zero. the total positive charge total negative charge.Formulas of Ionic CompoundsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeIonic compounds consist of positive and negative ions. have attractions called ionic bonds between positively and negativelycharged ions. have high melting points. are solids at room temperature.Properties of Ionic Compounds
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeWrite the ionic formula of the compound formedwith Ba2 and Cl ions.Study CheckGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeSubscripts in Formulas 2016 Pearson Education, Inc. 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.Select the correct formula for each of the following ionic compounds.1. Na and O2 A. NaOB. Na2OC. NaO23 2. Al and ClA. AlCl3B. AlClC. Al3Cl2 3 3. Mg and NA. MgNB. Mg2N3C. Mg3N2Study CheckGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeTo balance ionic charge in an ionic compound,total positive charge total negative chargeWriting Ionic Formulas from Ion Charges
2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.When naming an ionic compound, the name of the metal is written first and is the same asthe name of the element. the name of the nonmetal is the first syllableof the nonmetal name ide ending and iswritten second. a space is placed between the name of the metal andnonmetal ion.Naming Ionic CompoundsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 6.1 – Ions: Transfer of Electrons 6.2 – Writing Formulas for Ionic Compounds 6.3 – Naming and Writing Ionic Formulas 6.4 – Polyatomic Ions 6.5 – Molecular Compounds: Sharing Electrons 6.6 – Lewis Structures for Molecules and Polyatomic Ions 6.7 – Electronegativity and Bond Polarity 6.8 – Shapes and Polarity of Molecules 6.9 – Attractive Forces in CompoundsCh. 6 – Ionic and MolecularCompoundsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeNames of Some Ionic CompoundsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeLearning Goal Given the formula of an ionic compound, write thecorrect name; given the name of an ionic compound, write thecorrect formula.6.3 Naming and WritingIonic Compounds 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.
copper(II)copper(I)iron(II)iron(III)General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeCu2 Cu Fe2 Fe3 Pb2 Pb4 Cr2 Cr3 2016 Pearson Education, Inc.lead(II)lead(IV)chromium(II)chromium(III)A Roman numeral equal to the ion charge is placed inparentheses immediately after the metal name.Transition metals except for Zn2 , Cd2 , and Ag form twoor more positive ions (cations).Metals with Variable Charge 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeMetals with Variable ChargeGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeWrite the names of the following compounds.A. CaOB. Al2O3C. MgCl2Name the ionic compound K2O.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeStudy CheckNaming Ionic Compounds, K2O 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.
2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeName the ionic compound FeCl2. 2016 Pearson Education, Inc.Naming Ionic Compounds with Variable ChargeMetals, FeCl2General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeDetermine the charge of the metal ion in: MnF2Determination of Variable Charge 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeSnO2 2016 Pearson Education, Inc.Name the following ionic compound containing a variable charge metal.Study CheckGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeIon Charges, Periodic Table
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeWrite chemical formulas for the following compounds:A. nickel(II) sulfideB. aluminum chlorideC. iron(III) oxideStudy CheckGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 6.1 – Ions: Transfer of Electrons 6.2 – Writing Formulas for Ionic Compounds 6.3 – Naming and Writing Ionic Formulas 6.4 – Polyatomic Ions 6.5 – Molecular Compounds: Sharing Electrons 6.6 – Lewis Structures for Molecules and Polyatomic Ions 6.7 – Electronegativity and Bond Polarity 6.8 – Shapes and Polarity of Molecules 6.9 – Attractive Forces in CompoundsCh. 6 – Ionic and MolecularCompoundsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeWrite the formula for iron(III) chloride.The formula for an ioniccompound is written from, the first part of the namethat describes the metalion. the second part of thename that specifies thenonmetal ion.Subscripts are added tobalance the charge.Writing Formulas from theName of an Ionic CompoundWriting Formulas from theName of an Ionic Compound 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakePolyatomic IonsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeLearning Goal Write the name and formula for an ioniccompound containing a polyatomic ion.6.4 Polyatomic Ions 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakePolyatomic Ions, Names, and FormulasGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake Most polyatomic ions are made up of nonmetals (SO , NO , ClO ) Almost all of them have negative charges (-1, -2, -3, etc) NHAn ionic compound may contain a polyatomic ion (many-atomion) as one its cations or anions. A polyatomic ion is a group of covalently bonded atoms thathas an overall ionic charge.Polyatomic Ions 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.
2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeMagnesium nitrate 2016 Pearson Education, Inc.When writing formulas for ionic compounds containingpolyatomic ions, we use the same rules of charge balance asthose for simple ionic compounds.Writing Formulas for Compounds ContainingPolyatomic IonsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake2. When a related ion has one less oxygen,its name ends in ite.SO32 sulfitePO33 phosphiteNO2 nitrite3. Exceptions to these rules are the following:CN cyanide hydroxideOH1. Names of polyatomic ions end in ate.SO42 sulfatePO43 phosphate NO3 nitrateGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeWrite the formula for aluminum nitriteWriting Formulas with Polyatomic IonsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake4. Halogens form 4 polyatomic ions with oxygen.Each has a 1 charge.ClO4 perchlorate ClO3chlorateClO2 chlorite ClOhypochloriteNames of Polyatomic IonsNames of Polyatomic Ions 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeCompounds with Polyatomic IonsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.When naming ionic compounds containing polyatomic ions, first write the positive ion, usually a metal. write the name of the polyatomic ion second.Write the formula for sodium phosphate.copper(II) nitrateA. CuNO3B.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake2.Cu(NO3)2Select the correct formula for each.1. aluminum nitrateA. AlNO3B. Al(NO) 3Study CheckGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeC.C. 2016 Pearson Education, Inc.Cu2 (NO3)Al(NO3) 3 2016 Pearson Education, Inc.Recognizing polyatomic ions in a chemical formula helps to nameit correctly.Naming Compounds with Polyatomic IonsStudy Check
tin(IV) hydroxideA. Sn(OH)4B.FePO4General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeB.A. Ca(NO3)2 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.Pb3(PO3)2C.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeMgSO4B. 2016 Pearson Education, Inc.Name each of the following compounds containing polyatomic ions.A. MgSO3Sn4(OH)Name the following ionic compounds:C.Fe(OH)3Study CheckSn(OH)2C.Flow Chart, Naming Ionic CompoundsStudy CheckGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake4.Select the correct formula for each.3. iron(III) hydroxideA. FeOHB. Fe3OHStudy Check
Ba3(PO3)2NiCO3B.C.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeLearning Goal Given the formula of a molecular compound, writeits correct name; given the name of a molecular compound, writeits formula.6.5 Molecular Compounds:Sharing ElectronsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeFe2(SO4)3A.Name each of the following compounds:Study Check 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeMolecular compounds formwhen atoms of two or morenonmetals share electrons andform a covalent bond. valence electrons are sharedby nonmetal atoms to achievestability.A molecule forms when two ormore atoms share electrons.Covalent BondsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 6.1 – Ions: Transfer of Electrons 6.2 – Writing Formulas for Ionic Compounds 6.3 – Naming and Writing Ionic Formulas 6.4 – Polyatomic Ions 6.5 – Molecular Compounds: Sharing Electrons 6.6 – Lewis Structures for Molecules and Polyatomic Ions 6.7 – Electronegativity and Bond Polarity 6.8 – Shapes and Polarity of Molecules 6.9 – Attractive Forces in CompoundsCh. 6 – Ionic and MolecularCompounds 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeCommon Molecular CompoundsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.Several compounds may be formed from the same two nonmetals:CO2 carbon dioxideCO carbon monoxideWhen naming a molecular compound,the first nonmetal in the formula isnamed by its element name. second nonmetal is named usingthe first syllable of the namefollowed by ide.When a subscript indicates two ormore atoms of an element, a prefix isshown in front of its name.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeName the molecular compound NCl3.Naming Molecular Compounds, NCl3General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc. 2016 Pearson Education, Inc. The number of oxygen atoms present is indicated by the prefix. When the vowels o and o or a and o appear together, the firstvowel is omitted.NO nitrogen monoxide,Names and Formulas, Molecular CompoundsNames and Formulas, Molecular Compounds
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.A compound is covalent if 2 nonmetals are boundtogether.N2O: dinitrogen oxideA compound is ionic if a metal and a nonmetal arebound together OR the compound begins withK2O:potassium oxideNH4NO3:ammonium nitrateCompounds, Ionic or Covalent? 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeFlowchart, Naming CompoundsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeWrite the molecular formula for diphosphorus pentoxide.Name the molecular compound B2O3.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeStudy CheckStudy Check 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.
P2O5Cl2O72.3.AB.C.A.B.C.A.B.C.dichlorine heptoxidedichlorine oxidechlorine heptoxidephosphorus oxidephosphorus pentoxidediphosphorus pentoxidesilicon chloridetetrasilicon chloridesilicon tetrachlorideGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 6.1 – Ions: Transfer of Electrons 6.2 – Writing Formulas for Ionic Compounds 6.3 – Naming and Writing Ionic Formulas 6.4 – Polyatomic Ions 6.5 – Molecular Compounds: Sharing Electrons 6.6 – Lewis Structures for Molecules and Polyatomic Ions 6.7 – Electronegativity and Bond Polarity 6.8 – Shapes and Polarity of Molecules 6.9 – Attractive Forces in CompoundsCh. 6 – Ionic and MolecularCompoundsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeSiCl4 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.(NH4)3PO3C.N2O4General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeLearning Goal: Draw the Lewis structures for molecularcompounds or polyatomic ions.6.6 Lewis Structures forMolecules and Polyatomic IonsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeE.D. Cu2CO3BaCl2B. 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.Identify each compound as ionic or covalent and give its correct name.A. SO3Select the correct name for each compound.1.Study CheckStudy Check
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeA molecule is represented by a Lewis structure in which thevalence electrons of all the atoms are arranged to giveoctets.A molecule is represented by a Lewis structure in which the valenceelectrons of all the atoms are arranged to give octets. The shared electrons, or bonding pairs, are shown as two dots or asingle line between atoms. The nonbonding pairs, or lone pairs, are placed on the outside ofthe atoms.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeLewis Structures, Molecules 2016 Pearson Education, Inc. H, He (2 valence electrons) B (can only have 6) n 3 can have more than 8due to access to the 3d orbital. Exceptions: The Octet Rule: Most atoms want to have 8valence electrons. Atoms are the most stable when they have theelectron configuration of a noble gas. For H and He, that’s 2 electrons For n 2 and n 3 (Li through Ar) that is 8electrons (n 4 etc is higher. We won’t worry about thatnow.)The Octet RuleLewis Structures, MoleculesGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeThis gives it the electronconfiguration of He and therefore isvery stable.Each H acts as if it has 2 electrons.When two H atoms are far apart, they feel no attraction or repulsionto each other.As they approach each other, the electron on one H is attracted tothe proton (nucleus) of the other. And vice versa.The attraction is stronger than the repulsion between the twoelectrons.A covalent bond forms from each H sharing its electron with theother, creating the molecule: H2.The Simplest Molecule, H2 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.
2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.4. Complete the octets of terminal atoms (except H and He want2)5. Place leftover electrons on the central atom.6. If no unassigned electrons remain, and the central atomdoesn’t have an octet, use multiple bonds. Total valence electrons (step 1) minus # electrons used in bonding.1. Sum the valance electrons from all the atoms.2. Decide on atom connections and connect with a single bond.(“central atom” is usually written first in the formula.)3. Determine the number of valence electrons remainingGuide to Drawing Lewis StructuresGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeThe elements hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine andiodine exist as diatomic molecules.Elements, Diatomic MoleculesGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.6. If no unassigned electrons remain, and the central atomdoesn’t have an octet, use multiple bonds.5. Place leftover electrons on the central atom.4. Complete the octets of terminal atoms (except H and Hewant 2)Total valence electrons (step 1) minus # electrons used in bonding.3. Determine the number of valence electrons remaining2. Decide on atom connections and connect with a single bond.(“central atom” is usually written first in the formula.)1. Sum the valance electrons from all the atoms.Draw the Lewis structure for methane, CH4Drawing Lewis StructuresGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake# of bonds 8 – number of valence e’sThe number of electrons a nonmetal atom shares and the number ofcovalent bonds it forms are equal to the number of electrons it needs toachieve a stable electron configuration.Number of bonds
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeDraw the Lewis structure for BF3Study CheckGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.6. If no unassigned electrons remain, and the central atomdoesn’t have an octet, use multiple bonds.5. Place leftover electrons on the central atom.4. Complete the octets of terminal atoms (except H and Hewant 2)Total valence electrons (step 1) minus # electrons used in bonding.3. Determine the number of valence electrons remaining2. Decide on atom connections and connect with a single bond.(“central atom” is usually written first in the formula.)1. Sum the valance electrons from all the atoms.Molecules, Lewis StructuresGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.A double bond occurs when atoms share two pairs of electrons. forms when there are not enough electrons to completeoctets.A triple bond occurs when atoms share three pairs of electrons. forms when there are not enough electrons to completeoctets. 2016 Pearson Education, Inc.6. If no unassigned electrons remain, and the central atomdoesn’t have an octet, use multiple bonds.5. Place leftover electrons on the central atom.4. Complete the octets of terminal atoms (except H and Hewant 2)Total valence electrons (step 1) minus # electrons used in bonding.3. Determine the number of valence electrons remaining2. Decide on atom connections and connect with a single bond.(“central atom” is usually written first in the formula.)1. Sum the valance electrons from all the atoms.Double and Triple BondsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeDraw the Lewis structure for NH4 Study Check
4. Complete the octets of terminal atoms (except H and Hewant 2)5. Place leftover electrons on the central atom.6. If no unassigned electrons remain, and the central atomdoesn’t have an octet, use multiple bonds.4. Complete the octets of terminal atoms (except H and Hewant 2)5. Place leftover electrons on the central atom.6. If no unassigned electrons remain, and the central atomdoesn’t have an octet, use multiple bonds.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 6.1 – Ions: Transfer of Electrons 6.2 – Writing Formulas for Ionic Compounds 6.3 – Naming and Writing Ionic Formulas 6.4 – Polyatomic Ions 6.5 – Molecular Compounds: Sharing Electrons 6.6 – Lewis Structures for Molecules and Polyatomic Ions 6.7 – Electronegativity and Bond Polarity 6.8 – Shapes and Polarity of Molecules 6.9 – Attractive Forces in Compounds 2016 Pearson Education, Inc.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeLearning Goal: Use electronegativity to determine the polarity ofa bond.6.7 Electronegativity andBond PolarityTotal valence electrons (step 1) minus # electrons used in bonding.Total valence electrons (step 1) minus # electrons used in bonding. 2016 Pearson Education, Inc. 2016 Pearson Education, Inc.3. Determine the number of valence electrons remaining3. Determine the number of valence electrons remainingGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake2. Decide on atom connections and connect with a single bond.(“central atom” is usually written first in the formula.) 2016 Pearson Education, Inc.1. Sum the valance electrons from all the atoms.2. Decide on atom connections and connect with a single bond.(“central atom” is usually written first in the formula.)Draw the Lewis structure for HCN.Study Check1. Sum the valance electrons from all the atoms.Ch. 6 – Ionic and MolecularCompoundsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeDraw the Lewis structure for N2.Study Check
General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. Timberlake 2016 Pearson Education, Inc.ΔEN 0a nonpolar covalent bondΔEN between 0 and 2 a polar covalent bondΔEN 2an ionic bondΔEN 0a nonpolarcovalentbondand Biological Chemistry: Structures of Life, 5/eGeneral, Organic,Karen C. TimberlakeΔEN between 0 and 2 a polar covalent bondb d 2016 Pearson Education, Inc.A nonpolar covalent bond occurs between nonmetals. It is an equal sharing of electrons by the two bonding atoms. 2016 Pearson Education, Inc.Differences in electronegativity of atoms dictate what kind of bondforms between the atoms.General, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeNonpolar Covalent Bonds 2016 Pearson Education, Inc. The electrons will spend more time near the moreelectronegative atom. When the atoms in the bond are different, the moreelectronegative atom will “hog” the shared electrons inthe covalent bond.ElectronegativityPolarity of BondsGeneral, Organic, and Biological Chemistry: Structures of Life, 5/eKaren C. TimberlakeThe electronegativity of an atom is its ability to attract theshared electrons in a bond.Electronegativity
T
Ionic and Covalent Bonds Chemical bonds are formed when atoms lose, gain, or share valence electrons to completely fill their outermost electron shell. Ionic bonds occur when valence electrons of a metal atom are transferred to the atom of a nonmetal. Covalent bonds occur when nonmetal atoms share
Chem 103, Section F0F Unit VI - Compounds Part II: Covalent Compounds Lecture 15 The formation of covalent bonds Naming binary covalent and organic compounds The covalent bonding model Lecture 15 - Covalent Bonding Reading in Silberberg Chapter 2, Section 7 (pp. 62-64)-The Formation of Covalent Compounds Chapter 2, Section 8 (pp. 70-72)-Compounds, Formulas and Names
Shell Donax TU Shell Spirax S6 ATF UM Shell Donax TV Shell Spirax S6 ATF VM Shell Donax TX Shell Spirax S4 ATF HDX* Shell ATF XTR Shell Donax TA Shell Spirax S2 ATF D2 Shell ATF IID GREASES Shell Retinax CSZ Shell Gadus S4 V45AC Shell Albida HDX Shell Gadus S3 V460D Shell Retinax LX2 Shell
Section 3 Covalent and Metallic Bonds Key Concept Covalent bonds form when atoms share electrons. Metallic bonds form by the attraction of metal ions and the electrons around them. What You Will Learn Covalent compounds form when atoms of elements share electrons. Molecules are particles of covalent compounds and can be simple or complex.
8.3.a, 8.3.b W hat Are Covalent Bonds? Another type of bond is a covalent bond. A covalent bond forms when atoms share electrons. Covalent bonds most often form between atoms of nonmetals. Remember that most nonmetals can fill the outermost energy level by gaining an electron. When a covalent bond forms, both
Covalent Bonding 1. What is covalent bonding? 2. Ionic or covalent? a. CH 4 ionic or covalent b. Fe 2 O 3 ionic or covalent c. I 2 ionic or covalent d. H 2 O ionic or covalent e. BeCl 2 ionic or covalent 3. Lewis dot structures Helpful hints: Least electronegative compound goes in the middle
5.2 Covalent Bonds and the Periodic Table Covalent bonds can form between unlike atoms as well as between like atoms, making possible a vast number of molecular compounds. Water molecule, H2O, consists of two hydrogen atoms joined by covalent bonds to one oxygen atom.
ionic bonds are very different from those that have all covalent bonds. For example, compounds that have ionic bonds, such as the sodium chloride in table salt, are solids at room temperature and pressure, but compounds with all covalent bonds, such as hydrogen chloride and water, can be gases and liquids as well as solids. objeCtive 6 objeCtive 6
The Machinery, Automotive EMC, and Medical Devices directives and their harmonised standards do make some attempt to cover these issues, but fail to address them correctly [4]. Refer to the IEE Guidelines on EMC and Functional Safety [5], and articles on it [4], [6], [7], IEC 61508-2 [8] and IEC/TS 61000-1-2 [9] for more on these increasingly vital issues. These issues should be covered to be .
