SUPPLEMENTARY CONCENTRATION PROBLEMS

Transcription

1 SUPPLEMENTARY NENTRATIN PRBLEMS. Whole milk usually contains 5.0% milk fat by volume/volume. If you drink a 50.0 ml glass of whole milk, how much milk fat have you consumed? 5.0 % / fat ml milk 5.0 ml fat fat 00 ml milk 50.0 ml milk 5.0 ml fat fat 50.0 ml milk 00 ml milk.5 ml ml fat. A solution contains 5.0 g of potassium chloride in 55.5 g of water. alculate the weight/weight percent of solute in this solution. (Don t ignore the mass of the solute). % W/W Kl 5. g Kl 55.5 g water 5. g Kl 00.0 % W/W Kl. inegar is sold as a 5.0% (/) solution of acetic acid in water. Assuming that liquid volumes are additive, what volume of water must be added to 5 ml of acetic acid to produce synthetic vinegar? 5.0 % / 5.0 ml acetic acid 00 ml vinegar solution 5 ml acetic acid 00 ml solution acetic acid 00 5 ml acetic acid solution 00 ml vinegar 5 ml 85 ml or 0.9 L. Electrician s solder is 60.0% tin and 0.0% lead by mass. What is the mole ratio of the two elements? n n Sn Pb 60.0 g Sn 0.0 g Pb mol Sn ratio 0.9 mol Pb mol Sn 8.69 g Sn mol Pb 07.9 g Pb.6 Sn Pb mol Sn 0.9 mol Pb.6 Sn :Pb

2 5. Evaporation of a.7 g sample of slush yields a.58 g al salt residue. alculate the weight/weight percentage of calcium chloride in the slush. % W/W salt.58 g salt.7 g slush 9.5 % W/W salt the % W/W is9.5% al The recommended W/ percentage for a TSP solution used to clean walls before wallpapering is.7%. What mass of TSP is needed to make.0 L of this solution? m TSP 000 ml solution g TSP.7 g TSP 00 ml solution 7. The density of ethanol is g/ml. ow many grams of ethanol should be mied with 5 ml of water to make a.5% (v/v) miture? (8. g) m D g/ml ; % /.5 % /.5 ml 00 ml 0.05 ( ( 0.05) then solute solute m D solute 00 5 ml solute 5 ml 5 ml) solute solute solute solute solvent 0.5 ml m D g ml 00 solute ; ; 0.05 solute solute 0.60 ml 0.60 ml 8. g 0.5 ml solute

3 8. Ammonium nitrate, which is a major ingredient in fertilizers releases nitrate ion into the water. The World ealth rganization has set an upper limit of 0.0 ppm for infants. If an infant has a mass of.0 kg, what is the maimum allowable mass of nitrate ions that would be permitted in the infant s body tissues? m nitrate 0 mg nitrate.0 kg infant kg infant 0 mg nitrate

4 oncentrations and Dilutions Worksheet. What is the molarity of a solution in which 0.5 grams of sodium nitrate are dissolved in 65 ml of solution. (0.00 M) m? 0.5 g ; n m M 0.5 g g mol 0.65 L 0.00 mol/l M NaN NaN 0.00 M g/mol ; 65 ml 0.65 L. What will the volume of a 0.50 M solution be if it contains 5 grams of calcium hydroide? (680 ml) m? n m m ; M M 0.50 g 7.0 g mol 0.50 mol L L 0.50 g ; M a() a() 680 ml 7.0 g/mol ; 0.50 M 0.50 mol/l. ow many grams of ammonia are present in 5.0 L of a M solution? (. grams) 5.0 L ; m? n m mol L. g m M M ; N 7.0 g/mol ; m M 7.0 g mol M mol/l 5.0 L

5 . ow many grams of beryllium chloride are needed to make 5 ml of a M solution? (0.500 grams) 5.0 ml m? n m M m mol L g ; 0.5 L; m M M Bel 79.9g mol 79.9g/mol ; 0.5 L M mol/l 5. If 5.0 ml of water is added to 5 ml of a 0.5 M Na solution, what will the concentration of the diluted solution be? (0.5 M) 5 ml 0.5 L; 0.5 M ; 0.5 mol/l ; 5.0 ml 5 ml 50. ml? 0.5 mol L 0.5 L 0.50 L 0.5 mol/l 0.5 M 0.50 L

6 6. If 00.0 ml of water is added to a sample of 0.50 M Na solution until the final volume is 50.0 ml, what will the molarity of the diluted solution be? ( M) 50.0 ml L ; 0.50 M ; 0.50 mol/l ; 50.0 ml L? 0.50 mol L L 0.50 L mol/l M 7. ow much M l solution can be made by diluting 50.0 ml of 0.0 M l? (50.0 L) 50.0 ml L ; 0.0 M ; 0.0 mol/l ;? M mol/l 0.0 mol L L mol L 50.0 L 8. If a scientist has 5 ml of a.5 M Nal solution and she boils the water until the volume of the solution is 50. ml, what will the final concentration of the solution be? (.07 M) 5 ml 0.5 L ;.5 M ;.5 mol/l ;? 50. ml 0.50 L.5 mol L 0.5 L. mol/l 0.50 L.M

7 9. ow much water would I need to add to 500. ml of a.0 M Kl solution to make a.00 M solution? (700. ml).0 M ;.0 mol/l 500. ml L ; ; L L.00 M.00 mol/l.0 mol L L.00 mol L.0 L L L 700. ml 0. A clear solution is made from.5 L of 0.0 M Mgl and 0.50 L of water. alculate the resultant concentration of chloride ion. (0.60 M).5 L ; 0.0 M ; 0.0 mol/l [ l then ; ] 0.60 M l.0 L? 0.0 mol L.5 L 0.0 mol/l.0 L 0.0 mol Mgl L mol l mol Mgl 0.0 M

8 . The concentration of acetic acid,, in a sample of vinegar is determined to be mol/l. If the density of the acetic acid is.05 g/ml, calculate the volume/volume percent of acetic acid in the vinegar sample. (5.05 % /) D D D vinegar vinegar D vinegar mol/l ; m.05 g/ml ; M g/mol mol g L L vinegar mol 000 ml g/ml g/ml.05 g/ml % / acetic acid

9 SLUBILITY EXERISE Solubility (g/00 g water) Lead nitrate Potassium nitrate Ammonium chloride Sodium chloride Potassium chlorate Temperature ( ). State the solubility of the following substances at 0. (a) lead nitrate 65 g/00g (b) sodium chloride 7 g/00g. State the temperature at which 56 g of solute will dissolve in 00g of water for each of the following substances. (a) ammonium chloride 60 (b) potassium nitrate 8. What mass of potassium chlorate can be dissolved in 00 g of water at (a) 0 0 g (b) g. (a) What mass of ammonium chloride can be dissolved in 00 g of water at 90? 70 g (b) If you were to attempt to dissolve 00 g of ammonium chloride in 00 g of water at 90, what mass of the ammonium chloride would remain undissolved? 00 g 70 g 0 g 5. (a) What mass of lead nitrate can be dissolved in 00 g of water at 60? 9 g/00 g 86 g (b) If you were to attempt to dissolve 50 g of lead nitrate in 00 g of water at 60, what additional mass of the lead nitrate could still be dissolved? 86 g 50 g 6 g 6. ow much more lead nitrate could be dissolved in 00 g of water at 50 than sodium chloride at the same temperature?85 g 8 g 7 g 7. (a) If 00 g of potassium nitrate is dissolved in 00 g of water at 90 and allowed to cool, at what temperature would this solution be considered saturated? Saturated at appro. 55. (b) If the temperature were raised from the temperature you gave to your answer in (a), would the solution now be considered, unsaturated or supersaturated? Unsaturated. (c) If the temperature were lowered from the temperature you gave to your answer in (a), would the solution now be considered, unsaturated or supersaturated? Supersaturated. (d) In general if a solution has a concentration of solute which is above the solubility curve on the solubility graph, will the solution will be unsaturated, saturated or supersaturated? Supersaturated. (e) In general if a solution has a concentration of solute which is on the solubility curve on the solubility graph, will the solution will be unsaturated, saturated or supersaturated? Saturated

10 (f) In general if a solution has a concentration of solute which is below the solubility curve on the solubility graph, will the solution will be unsaturated, saturated or supersaturated? Unsaturated. (g) If the solution from (a) were cooled and allowed to crystallize, what mass of solute would have crystallized when the temperature reached 0? Solubility at 0 is appro. g/00 g or 6 g/00 g, therefore 00 g 6 g 6 g. 8. An unsaturated solution was prepared by dissolving 0.0 g of lead nitrate in 00 g of water at 0. (a) What mass of lead nitrate should be added to the solution in order to saturate it at 0? 56.5 g 0.0 g 6.5 g (b) If 50 g of water is added to the saturated solution at 0, what is its new concentration in grams/00 g of water? 56.5g 50 g 00 g ; 7.7 g 9. If a maimum of 9.0 g of calcium hydroide will dissolve in 00 g of water at 0, how much calcium hydroide could be dissolved in 8 g of water? 9.0 g 00 g 8 g ; 7.6 g 0. You are given a solution of potassium nitrate whose concentration is 60 g/00g (a) At what temperature will this solution be saturated? 8 (b) What would be the total mass of this saturated solution if it were made using 00 g of water? 60 g (c) If you were given a 00 g sample of this solution, i) how much of the 00 g total mass would be potassium nitrate 60 g sol't 60 g sol'n ; 7.5 g sol't 00 g sol'n ii) how much of the total mass would be water? mass of solvent 00 g 7.5 g 6.5 g iii) how much more solute can be dissolved if the temperature of the solution is 70? 0 g 00 g 6.5 g ; 87.5 g ; 87.5 g 7.5 g 50.0 g. Each of the following ten test tubes contains 0 ml of water at 60. The following masses of an unknown solid are placed in successive tubes; g, g, 6 g, 8 g, etc. up to 0 g in the last test tube. After the tubes are shaken, it is observed that the entire solid has dissolved in the first five test tubes, but that there is an increasing amount of undissolved solid in each of the remaining test tubes. (a) Which of the substances in the above solubility graph could be in the test tubes? Solubility is between 0 g / 0 ml and g /0 ml or 00 g/00g and 0 g/00 g at 5 which corresponds to potassium nitrate. (b) If the unknown is indeed the substance you named in part "a" above, what will happen if the solution in each of the test tubes is cooled to 0? At 0 the solubility falls to 0 g/ 00 g or g/ 0 ml, therefore the first test tube would be the only one with complete dissolution.

11 EXERISE A: USING TE SLUBILITY RULES. Underline which of lead (II) chloride, lead (II) sulphate or lead (II) nitrate is soluble?. When this solid compound is added to water write the ionic equation for this dissociation: Pb(N) (s) Pb N. Underline which of aqueous sodium ions, aqueous sulphate ions or aqueous acetate ions, will form a precipitate with the aqueous lead (II) ions if added to the above solution.. Underline which of calcium ions, sodium ions or silver ions will form a soluble compound with the ion underlined in the previous step. 5. Write the chemical equation for formation of the ions in # and # from the solid salt: NaS (s) Na S 6. Name the precipitate you epect to obtain from Step and Step : Lead (II) sulfate, PbS 7. Write the balanced chemical question by adding the aqueous reactants form Step to Step 5. Pb(N) NaS _ PbS (s) NaN 8. Write the net ionic equation for the reaction above. Pb S _ PbS (s) EXERISE B: 9. Write a dissociation equation for the dissolving of silver nitrate. AgN (s) Ag N 0. Write a dissociation equation for the dissolving of sodium bromide. NaBr (s) Na Br. Name the precipitate which will form if solutions of sodium bromide and silver nitrate are mied? Silver bromide, AgBr. Write the balanced chemical equation for the reaction between the aqueous reactants in Step 9 & 0. AgN NaBr _ AgBr (s) NaN. Give the net ionic equation for the reaction in Step. Ag Br _ AgBr

12 EXERISE : The objective is to find reactions that will allow one of two metal ions to form a precipitate by adding an appropriate solution to the miture. nce the first metal ion has been made to precipitate, you will then devise a method to precipitate the other metal ion.. Will a solution containing both barium and copper (II) ions contain anything other than water, barium ions and copper (II) ion? If yes, eplain why. They will contain anions from the original solid salts that produced them once they dissolved in water. 5. If it were added to a solution containing both barium and copper (II) ions, underline which of aqueous chloride ions, aqueous carbonate ions or aqueous sulphate ions will form a precipitate with one of aqueous barium ions or aqueous copper (II) ions (but not both). 6. Name the precipitate that will form if you were to carry out this addition. Barium sulfate, BaS 7. In order to make a solution of the ion you selected in Step 5, what compound would you dissolve in water? Remember that the compound you select will introduce another positive metal ion into the chemical soup containing the barium and copper (II) ions. In order that this introduced ion not cause etraneous precipitation reactions later in the eperiment, the compound you select now should contain a metal ion which will never precipitate regardless of the negative aqueous ions which may be currently present or be introduced later. Sodium sulfate, NaS 8. Write a dissociation equation for the dissolving of the compound selected in the previous step. NaS (s) Na S 9. Write a balanced chemical equation for the precipitation reaction that will occur if you add a solution of the compound selected in the previous step to a solution containing a miture of barium and copper (II) ions. Ba NaS _ BaS (s) Na 0. Underline which of Ba or u still remains in the solution.. Devise a method of precipitating this remaining positive ion from the solution, which won t cause precipitation with any of the other original positive ion that might still be present in solution? Add Na. Write the balanced chemical equation for this final reaction. u Na _ u() (s) Na

13 Reactions Involving Solutions. Silver nitrate solution may be used to precipitate the chloride ions from a sodium chloride solution. (a) Give the balanced, total ionic, net ionic equations and reaction type(s). AgN Nal Agl (s) NaN Ag N Na l Agl (s) Na N Ag l Agl (s) double displacement precipitation (b) alculate the volume of.50 M silver nitrate solution needed to precipitate 0.0 ml of.50 M sodium chloride solution. (0.080 L 80. ml) AgN.50 mol Nal L L L (0.05 mol) mol AgN mol Nal L.50 mol AgN (0.05 mol). Zinc will displace copper from a copper (II) nitrate solution. (a) Give the balanced, total ionic, net ionic equations and reaction type(s). Zn (s) u(n) Zn(N) u (s) Zn (s) u N u (s) Zn N Zn (s) u u (s) Zn single displacement (b) alculate the volume of.00 M copper(ii) nitrate needed to dissolve and oidize 5.00 g of zinc. (0.09 L 9 ml) u(n ) mol Zn 5.00 g 65.9 g 0.09L ( mol) mol u(n mol Zn ) L.00 mol u(n ( mol). Dinitrogen monoide will react with oygen gas and water vapor in the atmosphere to produce nitric acid. (a) Give the balanced, total ionic, net ionic equations and reaction type(s). N (g) (g) (g) N N (g) (g) (g) N synthesis )

14 (b) alculate the molarity of a nitric acid solution produced by the oidation of.00 g of dinitrogen monoide and subsequent dissolving of the product in 00. ml of water. (0.5 M) N mol N.00 g.0 g 0.05 M (0.068 mol) mol N mol N 0.00 L (0.6 mol). What mass of silver will be produced when an ecess of tin is added to 50.0 ml of M silver nitrate? ( g) Sn (s) AgN Ag (s) Sn(N) Mass(Ag) L g Ag mol AgN L mol Ag mol AgN g mol Ag 5. (a) Assuming that the scale formed on the bottom of a tea kettle forms only as a result of water hardness (a()) in the water supply, give the balanced, total ionic, net ionic equations and reaction type(s). a() (g) (l) a(s) a (g) (l) a(s) decomposition (b) Kettle scale (a) may be removed by the addition of an acid such as phosphoric acid. Give the balanced, total ionic, and net ionic equations as well as the reaction type(s). a(s) P (g) (l) a(p) a(s) 6 P (g) (l) a(p)(s) double displacement, decomposition (c) alculate the concentration of a phosphoric acid solution given that 50. ml of the solution is needed to remove 5.5 g of scale from the bottom of a tea kettle. (0.96 M) mol a mol P 5.5 g P g mol a 0.50 L (0.55 mol) (0.7 mol) 0.96 M

15 AIDBASE TERY. (a)give a balanced equation for the proton transfer reaction of a typical BrönstedLowry base such as N with water. N (g) (l) N (b) Identify the conjugate acid/base pairs in this system. base acid acid base (c) What is present in this system which accounts for the basicity of the solution? ions (d) ould the Arrhenius theory account for this basicity?. Eplain. No, since the N molecule does not contain hydroide ions which can be released upon dissolving. (e) Name the two BrönstedLowry acids present in this equilibrium system. & N (f) Name the two BrönstedLowry bases present in this equilibrium system. N &. Give the equation for the dissolving of pure S in pure. S S (a) Identify the conjugate acid/base pairs. acid base base acid (b) Would this reaction be considered an acid/base reaction under Arrhenius Theory? Eplain. No, because hydrogen ions are not reacting with hydroide ions and furthermore no Arrhenius base is present.. onsider the following acidbase reactions. Write an equation for each of the following reactions. Identify the acids and bases. Indicate one conjugate pair by single underlining their formulas and double underlining the other pair.

16 (a) P acting as a Brönsted acid in an aqueous solution. P (l) P (b) acting as a Brönsted base in an aqueous solution. (l) (c) the proton transfer reaction involving the acid and the base S S (l) S (d) the nonaqueous reaction in which hydrogen nitrate acts as a base and sulphuric acid acts as an acid. N S (l) N S. Some acids are have more than one proton ( ) available for donation, eg. S. These acids are called polyprotic. The loss of these protons may occur in successive steps. (a) Write the ionization equation for the BrönstedLowry acid S donating one proton ( ). S (l) S (b) Identify the conjugate acid/base pairs. acid base base acid (c) Identify the product of the above reaction that could function as either a BrönstedLowry acid or base. S (d) Write the ionization equation for the above product donating its remaining proton as a Brönsted Lowry acid. S (l) S

17 p Practice Worksheet. What is the p of a solution that contains 5 grams of hydrochloric acid (l) dissolved in.5 liters of water? [0.] l l p log [ n l m 5 g M 6.6 g mol ] log (0.6) mol/l.5l. What is the p of a solution that contains. grams of sulfuric acid ( S ) dissolved in 750 ml of water? [.5] S S n p log [ m. g M g mol ml S S (0.079 M) M ] log (0.059) mol/l. What is the p of a solution that contains. moles of nitric acid (N ) and.7 moles of hydrochloric acid (l) dissolved in 000 liters of water? [.5] N l n total n p log [..7.9 mol.9 mol mol/l 000 L n. mol n.7 mol N l ] log (0.009).5. If a solution has a [ ] concentration of M, is this an acidic or basic solution? Eplain. [6.5] p log [ Since the p ] log ( ) which is less than 7, that means that it will be slightly acidic.

18 5. An acidic solution has a p of. If I dilute 0 ml of this solution to a final volume of 000 ml, what is the p of the resulting solution? [6.0] [ ] 0 p log [ p ; ] log ( 0 6 M ) 6.0 mol L L 6. Determine the p of a 0.00 M N solution. [.7] N p log [ 0.00 M N ] log (0.00).7 7. Determine the p of a 0.00 M N solution. [.5] N p.7 ; p p ; 0.00 M N 0.00 L p Determine the [ ] concentration of an l solution with a p of.5. [5.6 0 ] l [ ] 0 p Determine the [ ] concentration of an S solution with a p of.5. [.8 0 ] [ S S ] 0 p 0.5 ( l M M S M) Determine the p of a. 0 M Na solution. [0.6] Na p log [ Na p ] log (. 0 M).7 6 M mol/l

19 . Determine the [ ] if a Na solution has a p of.65. [. 0 M] Na [ ] 0 p 0 Na M. If a solution is created by adding water to. 0 moles of Na and moles of Br until the final volume is L, what is the p of this solution? [0.5] Na n. 0 Since n n Na remaining. 0 n Na mol > n p log [ Br.6 0 L p Br n.5 0 and the mole raio is:, then Br is the limiting reagent mol mol.6 0 ] log ( mol.5 0 ).65 6 mol/l NaBr mol.6 0 mol

20 Titration Practice Worksheet. alculate the theoretical yield of produced by reacting 5.0 g of with 8. g of. m m ( ) 5.0 g mol.05 g g ( ) 8. g mol g 9.9 g mol mol (0.6 mol) 7.09 g mol mol mol 7.09 g mol (0. mol) is the LIMITING REAGANT and 9.9 g of is produced.. Fully label the titration curve given below with the equivalence point and label both aes if the graph below represents a titration where 5.00 ml of 0.50 M l is being titrated with Na. 5. alculate the concentration of the Na using data from the graph given above. From the graph, the equivalence volume of l 0.50 M 0.50 mol/l 5.00 ml L Na 0.50 mol l L L ( mol) 0.79 M Na? 5.0 ml L Na 5.0 ml Nal mol Na mol l L ( mol)

21 6. If the titration curve below is for the titration of 5.0 ml of sulphuric acid using sodium hydroide, calculate the concentration of the sodium hydroide solution. 0 p olume of Base Added (ml) The sharp vertical rise in the graph at 0 ml of base added represents the end point of the titration. To calculate the initial concentration of the acid, first read the p of the acid from the graph at the beginning of the titration [ [ S S Na ] 0 ] 0.0 M 0.0 p 0.05 L M M Na mol L ( mol) S (l) Na S mol Na mol S (0.005 mol) 0.00 L Na

22 SU Some Solution Review Questions. BSugar is dissolved in water. The sugar and water are respectively the (a) solvent & solution (b) solute & solvent (c) solution & solute (d) solute & solution. All solutions are (a) heterogeneous (b) cloudy (c) single phased (d) colorless. DPolar solvents will best dissolve solutes with the greater (a) London forces (b) hydrogen bonds (c) dipoledipole force (d) ionic bond. AWhich of the following substances will have the greater solubility in water at room temperature and pressure? (a) (b) (c) (d) 5. DEvaporation of a.7 g sample of slush yields a.58 g al salt residue. alculate the W/W percentage of calcium chloride in the slush. (a) 5.% (b) 5.% (c) 0.95% (d) 9.5% 6. inegar is sold as a 5.0% (v/v) solution of acetic acid in water. Assuming that liquid volumes are additive, what volume of water must be added to 5 ml of acetic acid to produce synthetic vinegar? (a) 00 ml (b) 90 ml (c) 85 ml (d).00 L 7. AThe water in a swimming pool is found to have a concentration of.0 mg/l of chlorine. This is the equivalent of (a).0 ppm (b) 0. ppm (c) 0.0 ppm (d) 0.00 ppm 8. DDetermine the molar concentration when.7 g of Nal are dissolved in water to make 0 ml of solution. (a) 0.50 (b).0 (c).0 (d) DA 0. M solution of l is prepared. The volume of a 00 ml sample is reduced to 60 ml through evaporation. The final concentration is (a) 0. (b) 0. (c) 0.8 (d).0 0. AA clear solution is made from.5 L of 0.0 M Mgl and 0.50 L of water. The resultant concentration of chloride ion is (a) 0.60 M (b) 0.57 M (c) 0.5 M (d) 0.7 M. A crystal of sodium chloride is dropped into a beaker containing a saturated solution of sodium chloride and some undissolved sodium chloride on the bottom of the beaker. What will be observed? (a) the undissolved ecess will dissolve (b) the added crystal will grow (c) no observeable change will occur (d) the added crystal will dissolve. AA saturated solution of KN may be made unsaturated by (a) raising the temperature (b) raising the pressure (c) adding a crystal of potassium nitrate (d) evaporating some of the water. DFor which of the following, can the metal ions be separated from one another by adding a solution of sodium hydroide? (a) cobalt nitrate and aluminum nitrate (b) barium nitrate and potassium chlorate (c) magnesium nitrate and nickel nitrate (d) potassium nitrate and iron(ii) nitrate. AWhich of the following best represents the net ionic equation for the reaction between Fel and Na?

23 (a) Fe (b) Fe (c) Fe (d) Fe l l l Na Na Fe()(s) Fe() Nal(s) Fe()(s) Nal Na Fe()(s) Nal 5. hemically, soap is a (a) a fat or oil (b) fatty acid (c) sodium salt of fatty acid (d) a miture of glycerine and fat 6. D"Temporarily" hard water may contain (a) Mgl (b) a (c) as (d) a( ) 7. BBubbles rise in a newly opened bottle of a carbonated beverage. This action is eplained by the fact that carbon dioide is less soluble in water when (a) pressure is increased. (b) pressure is reduced. (c) temperature is increased. (d) temperature is reduced. 8. Which solution contains the greatest mass of solute in 00 g of water? (a) A saturated solution of Nal at 00 (b) A saturated solution of Kl at 50 (c) A saturated solution of NaN at 5 (d) A saturated solution of KN at 5 (e) A saturated solution of Kr at Which of the following compounds would be most highly dissociated or ionized in water at room temperature and pressure (a) ammonia (b) acetic acid (c) hydrochloric acid (d) methyl alcohol 0. A solution which contains an equal number of hydrogen ions and hydroide ions is (a) an acidic solution (b) a basic solution (c) a neutral solution (d) a solid solution. BThe species responsible for the acidic properties of any aqueous acid is (a) the hydroide ion (b) the hydrogen ion (c) the negative ion (d) the oide ion. DWhich of the following could be used to determine whether or not an acid is strong or weak? (a) effect on litmus paper (b) measurement of solubility (c) determination of concentration (d) measurement of electrical conductivity. DWhich of the following statements concerning acids and bases is true? (a) All acids are strong electrolytes. (b) All bases are strong electrolytes. (c) All acid solutions with a concentration of greater than mol/l are strong acids. (d) The strongest acids are those which ionize to the greatest etent when dissolved in water.. An acidic solution, such as vinegar, (a) turns litmus paper blue (b) has a salty taste (c) has a sour taste (d) feels slippery

24 5. BIf the concentration of acid in a solution is decreased, the (a) [ ] increases and p decreases (b) [ ] decreases and p increases (c) [ ] and p both increase 6. BWhat is the concentration of in a solution whose p is? (d) [ ] and p both decrease (a) 0 M (b) 0 M (c) 0 0 M (d) M 7. The p of a 0.00 M solution of l is (a) (b) (c) (d) 8. What is the hydrogen ion concentration, [ ], of a 0.00 M solution of sodium hydroide, Na? (a) 0 M (b) 0 9 M (c) 0 M (d) 0 M 9. AAccording to the Arrhenius definition, one product formed when an acid reacts with a base is (a) a salt (b) an oide (c) a hydride (d) an anhydride 0. AWhat role does the water play in this reaction? l(g) (l) l (a) proton acceptor (b) electron acceptor (c) proton donor (d) elector donor. What is the conjugate base of the acid P? P (l) P (a) (b) (l) (c) P (d). BIn the reaction: N (l) N which is a conjugate acid base pair? (a) N, (b) N, N (c), N (d), N. Aow does the p of the miture change as hydrochloric acid, l, is slowly added to a solution of sodium hydroide, Na? (a) The p decreases and may go below 7 (b) The p increases and may go above 7 (c) The p decreases to 7 and stops (d) The p increases to 7 and stops. ow many grams of beryllium chloride are needed to make 5 ml of a M solution? (0.50 g) m n m ; m M ; M mol Bel 79.9g 0.5 L 0.50 g L mol Bel. The density of ethanol is g/ml. ow many grams of ethanol should be mied with 5 ml of water to make a.50% (v/v) miture? (8.6 g)

25 m ethanol D ; m D ; % / 00 ethanol water ethanol.50 % / 00 ethanol water.50 ml ethanol ; (ethanol 5) ethanol 00 ml ethanol 5 ml ethanol 0.5 ethanol ; ethanol 0.5 ethanol 0.60 ml then m D ; m g ml 0.60 ml What volume will be needed to dilute 0.0 ml of a M l solution to a 0.5 M l solution? (.0 L) ; mol Bel L 0.00 L.0 L 0.5 mol L ; 6. Indicate the solvent that will be best at dissolving the given solute in each of the following problems: Solute: Li Solvents: S or l l (polar solute, polar solvent) Solute: Solvents: N or l l (nonpolar solute, nonpolar solvent) 7. An acidic solution has a p of.00. If I dilute 0.00 ml of this solution to a final volume of ml, what is the p of the resulting solution? (6.0) [ ] 0 p log [ p 0 0 M 0 mol L ; L 6 ] log ( 0 ) L 0 6 M mol/l 8. What is the p of a solution that contains.0 moles of nitric acid (N ) and.70 moles of hydrochloric acid (l) dissolved in liters of water? (.58)

26 N l n total n p log [ mol n.0 mol n.70 mol N l.90 mol mol/l 000 L ] log (0.0090) If it takes 50.0 ml of 0.50 M K solution to completely neutralize 5 ml of sulfuric acid solution ( S ), what is the concentration of the S solution? ( 0.00 M) K S S 0.50 mol K L L (0.05 mol) 0.00 mol/l K S mol S mol K (0.05 mol) 0.5 L 0. If it takes 5 ml of M l to neutralize 5 ml of Na solution, what is the concentration of the Na solution? (0.006 M) l Na Nal Na mol l 0.05 L L (0.005 mol) mol/l mol l mol Na 0.5 L (0.005 mol). Using your knowledge of the BrønstedLowry theory of acids and bases, write equations for the following acidbase reactions and indicate each conjugate acidbase pair: a) N N b) N N ; N and N ; N and N c) P P P and P. If the titration curve below is for the titration of 5.0 ml of hydrochloric acid using aluminum hydroide, calculate the concentration of the aluminum hydroide solution.

27 0 p olume of Base Added (m The sharp vertical rise in the graph at 0 ml of base added represents the end point of the titration. To calculate the initial concentration of the acid, first read the p of the acid from the graph at the beginning of the titration (0.M) [ [ l Al() ] 0 0 ] 0.6 M 0.9 p 0.6 mol l L L ( mol) 0.0M Al() (l) All mol Al() mol l (0.000 mol) 0.00 L Na