A solution is a homogenous mixture of 2 or moresubstancesThe solute is(are) the substance(s) present in thesmaller amount(s)The solvent is the substance present in the largeramountSolution Solvent SoluteSoft drink (l)Air (g)Soft Solder (s)H2ON2PbSugar, CO2O2, Ar, CH4Snaqueous solutionsof KMnO4
An electrolyte is a substance that, when dissolved inwater, results in a solution that can conduct electricity.A nonelectrolyte is a substance that, when dissolved,results in a solution that does not conduct electricity.nonelectrolyte weak electrolyte strong electrolyte
Strong Electrolyte – 100% dissociationNaCl (s) Na+(aq) + Cl-(aq)H2OWeak Electrolyte – not completely dissociatedCH3COOH CH3COO-(aq) + H+(aq)Conduct electricity in solution?Cations (+) and Anions (-)
Ionization of acetic acidCH3COOH CH3COO-(aq) + H+(aq)A reversible reaction. The reaction canoccur in both directions.Acetic acid is a weak electrolyte because itsionization in water is incomplete.
Hydration is the process in which an ion is surroundedby water molecules arranged in a specific manner.δ+δ−H2O
Electrolytes• Substances thatdissociate into ionswhen dissolved inwater.• A nonelectrolyte maydissolve in water, but itdoes not dissociate intoions when it does so.
Electrolytes and NonelectrolytesSoluble ioniccompounds tend tobe electrolytes.
Electrolytes and NonelectrolytesMolecular compoundstend to benonelectrolytes,except for acids andbases.
Nonelectrolyte does not conduct electricity?No cations (+) and anions (-) in solutionC6H12O6 (s) C6H12O6 (aq)H2O
Electrolytes• A strong electrolytedissociates completelywhen dissolved in water.• A weak electrolyte onlydissociates partiallywhen dissolved in water.
AcidsThere are only sevenstrong acids:• Hydrochloric (HCl)• Hydrobromic (HBr)• Hydroiodic (HI)• Nitric (HNO3)• Sulfuric (H2SO4)• Chloric (HClO3)• Perchloric (HClO4)
Properties of AcidsHave a sour taste. Vinegar owes its taste to acetic acid. Citrusfruits contain citric acid.React with certain metals to produce hydrogen gas.React with carbonates and bicarbonatesto produce carbon dioxide gasCause color changes in plant dyes.2HCl (aq) + Mg (s) MgCl2 (aq) + H2 (g)2HCl (aq) + CaCO3 (s) CaCl2 (aq) + CO2 (g) + H2O (l)Aqueous acid solutions conduct electricity.
Identify each of the following species as a Brønsted acid, base, orboth. (a) HI, (b) CH3COO-, (c) H2PO4-HI (aq) H+(aq) + I-(aq) Brønsted acidCH3COO-(aq) + H+(aq) CH3COOH (aq) Brønsted baseH2PO4-(aq) H+(aq) + HPO42-(aq)H2PO4-(aq) + H+(aq) H3PO4 (aq)Brønsted acidBrønsted base
Solution StoichiometryThe concentration of a solution is the amount of solutepresent in a given quantity of solvent or solution.M = molarity =moles of soluteliters of solutionWhat mass of KI is required to make 500. mL of a2.80 M KI solution?volume of KI solution moles KI grams KIM KI M KI500. mL = 232 g KI166 g KI1 mol KIx2.80 mol KI1 L solnx1 L1000 mLx
Dilution is the procedure for preparing a less concentratedsolution from a more concentrated solution.DilutionAdd SolventMoles of solutebefore dilution (i)Moles of soluteafter dilution (f)=MiVi MfVf=
Other Concentration Terms• Dilute- a solution containing a small amount of solute• Concentrated- a solution containing more soluteSometimes relative concentrations of solutions areexpressed with the following terms:Saturated- solution of x which is in equilibrium withundissolved xUnsaturated- a solution which contains a lowerconcentration of solute than a saturated solutionSupersaturated- unstable situation in which the solutionactually contains more than the equilibriumconcentration of solute
How would you prepare 60.0 mL of 0.200 M HNO3from a stock solution of 4.00 M HNO3?MiVi = MfVfMi = 4.00 M Mf = 0.200 M Vf = 0.0600 L Vi = ? LVi =MfVfMi= 0.200 M x 0.0600 L4.00 M= 0.00300 L = 3.00 mLDilute 3.00 mL of acid with water to a total volumeof 60.0 mL.
Types of Chemical Reactions1. Precipitation2. Acid-Base3. Oxidation-Reduction-virtually all chemical reactions can be put intoone of these classes
Precipitation ReactionsPrecipitate – insoluble solid that separates from solutionmolecular equationionic equationnet ionic equationPb2++ 2NO3-+ 2Na++ 2I-PbI2 (s) + 2Na++ 2NO3-Na+and NO3-are spectator ionsPbI2Pb(NO3)2 (aq) + 2NaI (aq) PbI2 (s) + 2NaNO3 (aq)precipitatePb2++ 2I-PbI2 (s)
Precipitation of Lead IodidePbI2Pb2++ 2I-PbI2 (s)
Writing Net Ionic Equations1. Write the balanced molecular equation.2. Write the ionic equation showing the strong electrolytescompletely dissociated into cations and anions.3. Cancel the spectator ions on both sides of the ionic equation4. Check that charges and number of atoms are balanced in thenet ionic equationAgNO3 (aq) + NaCl (aq) AgCl (s) + NaNO3 (aq)Ag++ NO3-+ Na++ Cl-AgCl (s) + Na++ NO3-Ag++ Cl-AgCl (s)Write the net ionic equation for the reaction of silver nitrate withsodium chloride.