Presentation on theme: "Solutions Solute – what is dissolved"— Presentation transcript:
1Solutions Solute – what is dissolved Solvent – what the solute is dissolved into.Aqueous solutions have water as the solvent.
2Water solubility depends on: Polarity of solute and solvent.Relative attractions of the ions for each other as opposed to the ions attraction for the water molecules
3Strong electrolytesA solution of a strong electrolyte is able to conduct a current efficientlyThe ionic substance completely ionizes. Soluble salts, strong acids, strong bases
4Weak ElectrolytesSolutions that do not conduct electricity efficiently.Only a small amount of the ionic compound ionizes Insoluble or slightly soluble salts, weak acids or bases
5NonelectrolytesSolutions that do not conduct electricity.Solute is polar but not ionic so no ions can be produced.Molecular compounds in solution.
6Molarity (M)M = moles of soluteliters of solution
7A solution of ethanol is prepared by dissolving 75 A solution of ethanol is prepared by dissolving 75.0 mL of ethanol (density = 0.79g/mL) in enough water to make mL of solution. What is the molarity of this solution?
8Calculate the concentration of all ions present in a solution made from 1.00g of K2SO4 in mL of solution.
9How would you prepare 500 mL of a 0 How would you prepare 500 mL of a 0.500M solution of sodium carbonate from the pure solid?
10DilutionsAdding water to a stock or concentrated solution in order to prepare a lower molarity solution.Moles of solute before dilution =moles of solute after dilution
11M=molarity; V=volume M1xV1 = moles of solute before dilution M2xV2 = moles of solute after dilutionM1xV1 = M2xV2
12How would you prepare 250 mL of 6 How would you prepare 250 mL of 6.0M sulfuric acid from concentrated (18M) sulfuric acid?
13Precipitation Reactions When two solutions are mixed an insoluble product is formed.To predict the product of these reactions solubility rules must be known.Table 4.1 p. 152
14Al(NO3)3(aq) + Ba(OH)2(aq) CaCl2(aq) + Na2SO4(aq) Write the balanced molecular, the complete ionic, and the net ionic equations for the followingFeSO4(aq) + KCl(aq)Al(NO3)3(aq) + Ba(OH)2(aq)CaCl2(aq) + Na2SO4(aq)K2S(aq) + Ni(NO3)2(aq
15Solution Stoichiometry Identify reactants and productsBalance net ionic equationCalculate moles of reactantsDetermine limiting reactantCalculate moles of productConvert to grams or other unit
16What volume of 0.100M Na3PO4 is required to precipitate all the lead(II) ions from mL of 0.250M Pb(NO3)2 ?
17What mass of barium sulfate can be produced when 100. 0 mL of a 0 What mass of barium sulfate can be produced when mL of a 0.100M solution of barium chloride is mixed with mL of a 0.100M solution of iron(III) sulfate?
18Acid –Base Reactions Acid- proton donor Base – proton acceptor Acid + base salt + waterNeutralization reaction.
19HNO3(aq) + Al(OH)3 HC2H3O2(aq) + KOH(aq) Ca(OH)2(aq) + HCl(aq) Write the balanced molecular, the complete ionic, and the net ionic equations for the followingHNO3(aq) + Al(OH)3HC2H3O2(aq) + KOH(aq)Ca(OH)2(aq) + HCl(aq)
20Hydrochloric acid (75. 0 mL of 0. 250M) is added to 225. 0 mLof 0 Hydrochloric acid (75.0 mL of 0.250M) is added to mLof M Ba(OH)2 solution. What is the concentration of the excess H+ or OH- ions left in solution?
21Oxidation-Reduction Reactions Reactions where one or more electrons are transferred.The oxidation state or number of an element will change during the reaction.Rules for assigning oxidation numbers – Table 4.2 p.167
22Species Oxidized - increase in oxidation state , lose electron(s) and act as the reducing agent. Species Reduced - decrease in oxidation state, gain electron(s) and act as the oxidizing agent.
23Assign oxidation states to all atoms UO22+As2O3NaBiO3Cl2Mg2P2O7
24Specify which of the following are redox reactions, identify the oxidizing agent, the reducing agent, the species being oxidized and the species being reducedCu(s)+ 2Ag+(aq) 2Ag(s) + Cu2+(aq)HCl(g) + NH3(g) NH4Cl(s)SiCl4(l)+ 2Mg(s) 2MgCl2(s) + Si(s)
25Balancing Redox Equations Write separate half reactionsBalance each half reactionElements except H and OOxygen using waterHydrogen using H+Charge using electrons
26Balancing Redox Equations Equalize electrons transferred by multiplying half reactions by whole numbers.Add half reactions togetherIf the reaction is in a basic environment neutralize the H+ ions with OH- ions.
27Balance the following in acid solution Cr2O7(aq)+ Cl-(aq) Cr3+(aq) + Cl2(g)Pb(s)+PbO2(s)+H2SO4(aq)PbSO4(s)Mn2+(aq)+NaBiO3(s)Bi3+(aq)+MnO4(aq)
28Balance the following in basic solution Cr(s)+CrO42-(aq) Cr(OH)3(s)MNO4-(aq)+ S2-(aq) MnS(s) + S(s)CN-(aq)+MnO4-(aq)CN-(aq)+MnO2(s)