Presentation on theme: "Ionic Bonds And Ionic Compounds"— Presentation transcript:
1 Ionic Bonds And Ionic Compounds Section 7.2Ionic BondsAndIonic Compounds
2 Formation of an Ionic Bond CompoundA chemical combination of two or more different elementsBinary compounds when there are exactly two different elements
3 Formation Na + Cl Na+ + Cl- + energy P. 210 shows chemical reactions that form ionic bonds and release energySodium and chlorine gas produce a white crystalline solidNa + Cl Na+ + Cl- + energyThis is called a chemical equation.
4 What Happened? + Sodium transferred one valence electron to chlorine. [Na]+ + [Cl]- + energy+This is the electron-dot structures
5 Types of Ionic Compounds Electrostatic force holds the charged atoms together is the ionic bond.Metal and non-metal ionic bond are called oxides.Most other ionic compounds are called salts.
6 Names Sodium + Chlorine forms sodium chloride Sodium is a metal Chlorine is a non-metalChange chlorine to chloride in the name of the compound
7 p. 210 bRibbon of magnesium metal burns in air, it forms the ionic compound magnesium oxide.Magnesium is a metalOxygen is a non-metalNotice the name, oxygen became oxide.Is this a binary ionic compound?
8 Questions Explain how an ionic compound forms from these elements sodium and nitrogenlithium and oxygenstrontium and flourinealuminum and sulfur
9 Challenge Question11. Explain how elements in group 1 and group 15 combine to form an ionic compound.
10 Properties of Ionic Compounds Physical structureRatio of positive and negative ionsIons are packed into repeating patternBalance the forces of attraction and repulsion between ions* No single unit of Na and Cl exists, there are many Na+ and Cl- ions in a 1 to 1 ratio.
13 Crystal Lattice Three dimensional geometric arrangement of particles Each positive ion is surrounded by negative ions and each negative ion is surrounded by positive ionsThe number of ions and the ratio determine the size and shape
14 Examples Minerals More than 1/3 of all known minerals are silicates HalidesBoratesCarbonatesWhat elements do you think are in these?
15 Physical Properties Melting point Boiling point Hardness Depends on how strong the ionic attraction isIonic crystals are hard, rigid, brittle solids, hard to break apart – high melting and boiling pointsConduct electricitySolids: ions are locked into place, cannot conduct electricityMelt or dissolve solids into solutionsElectrolytes are solutions that conduct electricity and important to humans
16 Energy Endothermic Energy is absorbed Exothermic Energy is released Formation of ionic compoundsForms more stable system so lower energy state, release energy
17 Math / GraphMake a scatterplot of Interionic Distance and Lattice EnergyTitle_______________(kJ/mol)(μm)
18 Lattice Energy and Interionic Distance Ionic Radius: the sum of the radii of each ionLi+: 76 μmF-: 133 μmCl-: 181 μmI-: 220 μmFindLiF, LiCl, LiILattice EnergyLiF: kJ/molLiCl: kJ/molLiI: kJ/molPlot each ionic compoundUse a different color for each point and label
19 RelationshipUse your graph to describe the relationship between the interionic distance and lattice energy.Fill in the blanks:As interionic distance ________, lattice energy ___________.
20 Lattice EnergyEnergy required to separate 1 mol of the ions in an ionic compoundThe greater the lattice energy, the stronger the force of attraction ( harder to separate)
21 Predict Use your graph to estimate the lattice energy for LiBr. The ionic radius of Br- is 196 μm.
22 Patterns in Lattice Enery Make a line graph of compound versus lattice energy (kJ/mol)Make each set of compoundsa different color, 4 colorsLi set – blueNa set – redK set – greenRb set - orange
23 Compound Lattice Energy LiF LiCl LiBr LiI -1032 -852 -815 -761 NaF NaClNaBrNaI-926-786-752-702KFKClKBrKI-813-717-689-649Make each set of compounds a different colorLi set – blueNa set – redK set – greenWrite a few sentences to describe any pattern you see.
24 Prediction Predict the shape of the graph of the lattice energies of RbF, RbCl, RbBr, RbI
25 Add to Graph in OrangeAdd the Rb___ compounds to your graph in orange to verify your prediction.RbF 774
26 SummaryIonic compounds contain ionic bonds formed by the attraction of oppositely charged ions.Ions in a ionic compound are arranged in repeating patterns known as a crystal lattice.Ionic compounds properties are related to ionic bond strength.
27 Ionic compounds are electrolytes; they conduct an electric current in the liquid phase and in aqueous solution.Lattice energy is the energy needed to remove 1 mol of ions from its lattice.
28 QuestionsExplain how an ionic compound made up of charged particles can be neutral?Describe the energy change associated with ionic bond formation, and relate it to stabillity.Identify three physical properties of ionic compounds that are associated with ionic bonds, and related them to bond strength.
29 Explain how ions form bonds, and describe the structure of the resulting compound. Relate lattice energy to bond strength.Use electron configurations, orbital notations and electron dot structures to represent the formation of an ionic compound from the mental strontium and the non-metal chlorine.
30 QuestionUsing the elements aluminum and oxygen, determine the formula for the ionic compound.Extension: Use Fe2+ and Fe3+ to combine with O2-Determine the formula for the ionic compounds.
31 Each Student List a metal and a non-metal Exchange papers and determine the ionic compound formed between them.
32 Exit TicketDetermine the ionic compound formed from Mg and Cl and explain how it was formed.Include its ratio