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Workbooklet & Notes
Unit on Solutions
Why did he jump into thehomogeneous mixture?
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STUDENT NOTES Solution Characteristics and Solubility Factors
A solution consists of two parts:
(1) ____________________________________________________
(2) ____________________________________________________
An aqueous solution has ______________________________________
Solute SolventExample: NaCl (aq)
Characteristics of Solutions
Solutions…are __________________ mixtures;
do not ____________________;
do not ____________________;
can _______________________;
can _______________________
Solubility Factors
(1) “Like Dissolves Like”
Polar solvents will dissolve _____________________________________
Why? ______________________________________________________
Non-polar solvents will dissolve _____________________________
Why? _____________________________________________________
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CHROMATOGRAPHY: _______________________________________________________
(2) Temperature
As temperature increases, (s) and (l) solutes ___________________________
(g) solutes _________________________________
(3) Pressure
As pressure increases, (s) and (l) solubility _________________________
(g) solutes _________________________________
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STUDENT NOTES on Table F
Soluble ______________________________________________
Insoluble ______________________________________________
Compounds that contain X are ______________________________________________ always water-soluble
Compounds that contain Y are ______________________________________________ usually water-soluble
Compounds that contain Z are ______________________________________________usually insoluble in water
NH4OH _________
Hydroxides…_________________________________
Ag2SO4 _________
Sulfates…_____________________________________
CuSO4 _________
Sulfates…_____________________________________
Mg(OH)2 _________
Hydroxides…__________________________________
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STUDENT NOTES Table G
Table G is used to determine the ____________________________________________________
______________________________________________________________________________
Solubility curves for solids have _____________________________________
Solubility curves for gases have _____________________________________
A is on the KNO3 line. Mass of solute dissolved: _______ Temperature of Water: ______
______________________________________________________________________________
B is below the KNO3. Mass of solute dissolved: _______ Temperature of Water: ______
______________________________________________________________________________
C is above the KNO3 line. Mass of solute dissolved: _______ Temperature of Water: ______
______________________________________________________________________________
What mass of NH4Cl can be maximally dissolved in the following samples of water?
grams H2O o C grams NH4Cl
100 g H2O 75 ___________
50 g H2O 75 ___________
200 g H2O 75 ___________
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NOTES Further Applications of Table G
A solubility curve for Compound Q
1. A supersaturated solution contains 80.0 grams of Q in 100 grams of water at 20.0 oC. When disturbed, its excess solute crystallizes out of solution, leaving a saturated solution at 20.0oC. What mass of Q crystallizes out?
mass of solute mass of solutein supersaturated - in saturated = excess
2. A solution at 40.0oC contains 10.0 grams of Q dissolved in 100.g of water. How much more Q can the solution hold at 40.0 oC?
mass of solute mass of solutein saturated - in unsaturated = additional amount
3. A saturated solution of Q in 100. grams of water at 60.0oC quickly cools down to 20.0oC. How much Q crystallizes out?
mass of solute mass of solutein saturated 60oC - in saturated 20oC = amount crystallizing
4. A saturated solution of Q in 200. grams of water at 40.0 ˚C is heated to 60.0 ˚C. What additional mass of Q can be dissolved in the solution
in 100 grams of water:
mass of solute mass of solutein saturated 60˚C in saturated 40.0˚C = amount crystallizing
_____g = x g100 g water 200 g water
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STUDENT NOTES Molarity
Molarity is a measure of ______________________________
The units are _______________________________________
This is written _______________________________
Table H formula:
Example 1
What is the concentration, in mol/L, of a 3.00 L solution which contains 2.30 moles of solute?
Molarity = moles solute / L solution
Example 2
What is the volume of a 0.200 M aqueous solution that contains 0.900 moles of solute?
Molarity = moles solute / L solution
Example 3
The volume of a solution of 0.400 M NaCl (aq) is 375 mL. Calculate the number of moles of NaCl that the solutions contains.
Molarity = moles solute / L solution
Example 4
20.0 grams of NaOH (gram formula mass = 40.0 g/mol) is dissolved in 5.60 L of solution.What is the concentration of the solution?
Molarity = moles solute / L solution
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STUDENT NOTES on PPM
Parts per million (ppm) is a measure of _____________________________________________
Table T formula:
Mass of solution =
Example 1
It has been determined that human beings can detect the presence of sodium chloride in water if the concentration of the salt is at least 4000 ppm.
A small pool contains 550,000 grams of salt water. What is the minimum mass of salt that needs to be dissolved in this volume in order to be detected by human taste buds?
ppm = mass of solute x 1,000,000mass of solution
Example 2
A beaker of KI (aq) contain 2.50 x 10-2 grams of KI (s) and has a concentration of 35.0 ppm. What is the mass of the KI (aq)?
ppm = mass of solute x 1,000,000mass of solution
Example 3
What is the concentration, in ppm, of NaCl in water of solution that was created by dissolving 75.0 grams of the salt in 350.0 grams of water?
ppm = mass of solute x 1,000,000mass of solution
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BOILING POINT ELEVATION vs FREEZING POINT DEPRESSION
A solution will have a____________________________________________ than will its solvent.
The greater the concentration of a given solution, ____________________________________
_________________________________
Pure water H2O (l) Salt Water NaCl (aq)
Ionic vs Covalent Solutes
1 mole of an ______________________________________________________than
1 mole of a__________________________________
The greater the concentration of ______________________________________________
_____________________________________________
The____________________________, the MORE the _____________________________
< < __________ ___________ ____________
Therefore 0.100 M ___________________________________________________than does
0.100 M ___________________
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Dilutions
If you change the volume of a solution, ________________________________________
Table T Formula:
Notice that the number of moles _____________________________________
Example 1
You have 100. mL of 0.400 M NaCl (aq). You add enough water to change the volume to 109. mL. What is the new concentration of the solution?
Example 2
After changing the volume from 300. mL to 510. mL, the concentration of a KCl (aq) solution changes to 0.500 M. What was the original concentration?
Example 3
35.0 mL of water is added to 215. mL of 0.200 M LiOH (aq). What is the new concentration of the solution?
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STUDENT NOTES Expressing Concentration as Percent by Mass Composition
% composition = mass of part x 100% mass of whole
= _____________ x 100%
mass of _____________ = _____________ + _____________
Example: Determine the % by mass composition of solute in a solution containing 48. grams of potassium nitrate dissolved in 150. g of water.
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exercises on solution criteria and solubility factors
1. The attraction between water molecules and an Na+ ion or a Cl- ion occurs because water molecules are[1] linear [3] polar[2] symmetrical [4] nonpolar
2. What happens when an ionic compound is dissolved in water?[1] a negatively charged metal ion is attracted to the hydrogen side of the water.[2] a positively charged metal ion is attracted to the hydrogen side of the water.[3] a negatively charged nonmetal ion is attracted to the hydrogen side of the water.[4] a positively charged nonmetal ion is attracted to the hydrogen side of the water.
3. As the chemical similarity of solvent and solute increases, the solubility generally[1] increases [2] decreases [3] increases
4. Which has the least effect on the rate of solution of a solid in a liquid?[1] amount of surface area [3] pressure[2] agitation [4] temperature
5. A true solution has all the following properties except[1] it is clear[2] it will not separate on standing[3] a beam of light passing through it will be visible[4] it will pass through a filter
6. Under which set of conditions will O2 (g) be least soluble in water?[1] at 20˚C and 1.0 atm [3] at 20˚C and 2.0 atm[2] at 40˚C and 1.0 atm [4] at 40˚C and 2.0 atm
7. The solubility of which of the following elements in water is least affected by changes in pressure?[1] iodine [3] oxygen[2] chlorine [4] nitrogen
8. Which of the following substances is most soluble in water?[1] O2 [3] CO2[2] HI [4] CF4
9. Which of the following graphs represents the relationship between temperature andthe solubility of gases in water?
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ADVENTURES IN SOLUBILITY
1. Garry Gasbag is quite happy with the CO2 (g) content of his RC Cola, but feels that it should be much sweeter. He therefore decides to warm up the cola on the stove so that he can dissolve additional sugar, C11H22O10 (s), into the solution.
a. Will Billy’s method allow him to sweeten his cola? Explain why or why not.
b. With respect to the CO2 (g) dissolved in solution, give one drawback to warming the cola.
2. A scuba-diving papparazzi is under water, 40 meters below Lady Gaga’s luxury yacht, getting ready to swim up and snap some shots of the vacationing diva when he is surprised by some of Gaga’s little monsters, a group of vicious sharks! Terrified, he forgets his scuba training and surfaces much too rapidly!!
a. As he swims upward, what is happening to the pressure exerted by the surrounding water on the quickly ascending papparazzi?
b. As this happens, explain why nitrogen bubbles rapidly form in his blood.
3. Edwina Powerplant has chlorinated Grandpa Powerplant’s swimming pool, which holds a total of 2.47 x 108 grams of water, in honor of his 77th birthday, which he will celebrate tomorrow. As a C- student in chemistry, Edwina is confident that the 2000 grams of chlorine tablets that she added will result in a free available chlorine concentration between 2.0 ppm and 4.0 ppm, and certainly not in excess of 5.0 ppm, which would burn poor Grandpa’s eyes. But is she correct?
Determine whether the tears in Grandpa Powerplant’s eyes will be tears of joy when he realizes what Edwina has done after his morning swim tomorrow. SHOW WORK.
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4. A unsaturated solution consists of 75.0 grams of potassium nitrate in 100. grams of
water at 50˚C. Using Table G, calculate the minimum mass of water that has to evaporate from the solution in order to produce a saturated solution.
5. In its desalination plants along the coast of the Indian Ocean, Saudi Arabia removes NaCl (s) from seawater in order to produce drinking water for its population. A new proposal for the next generation of desalination plants calls for removal of NaCl (s) by passing seawater through a vacuum chamber and decreasing the pressure on the water to near zero. Will NaCl (s) crystallize out of the water? Explain why or why not.
6. A beaker of water contains a certain mass of sodium acetate, NaC2H3O2.
If a single crystal of sodium acetate is dropped into solution, explain what will be observed in the beaker if the the solution is
a. unsaturated.
b. saturated.
c. supersaturated.
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Exercises on Table F
A. Selected Response
(1) Which solid is most soluble in water at room temperature? [1] aluminum nitrate [3] silver acetate [2] calcium sulfate [4] zinc phosphate
(2) Which substance is most soluble in water? [1] barium carbonate [3] ammonium sulfide [2] lead (II) chloride [4] silver chromate
(3) Which silver compound is most soluble in water? [1] silver acetate [3] silver nitrate [2] silver chloride [4] silver sulfate
(4) Which is least likely to precipitate from a double replacement reaction? [1] mercury (I) carbonate [3] zinc hydroxide [2] iron (III) sulfate [4] silver hydroxide
(5) Which of the following aqueous solutions would react with NaOH (aq) to produce a precipitate? [1] BaCl2 [3] FeSO4
[2] KNO3 [4] Na3PO4
(6) Zinc ions would react to form an insoluble precipitate with ions of [1] sulfate [3] chloride [2] sulfide [4] nitrate
(7) Sulfate compounds are [1] always soluble in water [3] usually insoluble in water [2] usually soluble in water [4] always insoluble in water
(8) Which compound is the least soluble in water? [1] K2CrO4 [3] Pb(NO3)2
[2] AgC2H3O2 [4] FeCO3
(9) The compound XOH is insoluble in water. X could be [1] Mg2+ [3] Ag+
[2] Ba2+ [4] K+
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B. Precipitation Reactions
Predict the formulas of the products of the following double replacement reactions. Then using the solubility guidelines of Table F, circle the product that is the insoluble precipitate.
(1) CaCl2 (aq) + K2SO4 (aq) --> ________ + ________
(2) NaOH (aq) + AgNO3 (aq) --> ________ + ________
(3) KI (aq) + Pb(C2H3O2)2 (aq) --> ________ + ________
(4) (NH4)2CrO4 (aq) + CuSO4 (aq) --> ________ + ________
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Exercises with Table G
(1) A solution contains 100 grams of a compound in 100 grams of water at 50˚C. The solution could be[1] a supersaturated solution of NaNO3 (aq)[2] a saturated solution of NaNO3 (aq)[3] a supersaturated solution of KNO3 (aq)[4] a saturated solution of KNO3 (aq)
(2) As more crystals of NaNO3 (s) are added to a saturated solution of NaNO3 at 40˚C, the concentration of the solution[1] increases [2] decreases [3] remains the same
(3) Based on Reference Table G, which of the following substances is most soluble at 50˚C,[1] KClO3 [3] NaCl[2] NH3 [4] NH4Cl
(4) How many grams of KNO3 would be needed to saturate 200 grams of water at 70˚C?[1] 43 grams [3] 134 grams[2] 86 grams [4] 268 grams
(5) Which compound’s solubility decreases most rapidly when the temperature increases from 50˚C to 70˚C?[1] NH3 [3] SO2
[2] HCl [4] KNO3
(6) According to Table G, how does a decrease in temperature from 40˚C to 20˚C affect thesolubility of NH3 and KCl?[1] The solubility of NH3 decreases, and the solubility of KCl decreases.[2] The solubility of NH3 decreases, and the solubility of KCl increases.[3] The solubility of NH3 increases, and the solubility of KCl decreases.[4] The solubility of NH3 increases, and the solubility of KCl increases.
(7) Base your answer to the following question on the diagram below which representsthe solubility curve of salt X. The four points on the diagram represent four solutions ofsalt X.
Which point represents a supersaturated solution of salt X?[1] A [2] B [3] C [4] D
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(8) What mass of potassium chlorate can be dissolved in 50 grams of water at 10˚C?[1] 4 grams [3] 15 grams[2] 8 grams [4] 30 grams
(9) Which of the following solutions is classified as unsaturated?[1] 40 grams of NaNO3 (s) in 50 grams of H2O at 10˚C[2] 25 grams of KCl (s) in 50 grams of H2O at 75˚C[3] 135 grams of KI (s) in 100 grams of H2O at 20˚C[4] 28 grams of KNO3 (s) in 100 grams of H2O at 60˚C
(10) What is the total mass of potassium chloride needed to saturate exactly 300 grams of water at 10˚C[1] 60 [3] 80[2] 70 [4] 90
(11) A solution contains 14 grams of KCl in 100. grams of water at 40˚C. What is the minimum amount of KCl that must be added to make this a saturated solution?[1] 14 grams [3] 25 grams[2] 19 grams [4] 44 grams
(12) 100 grams of water is saturated with ammonium chloride at 50˚C. The number of gramsof ammonium chloride that must be added to saturate the solution at 70˚C is[1] 0.10 grams [3] 10 grams[2] 0.20 grams [4] 20 grams
(13) Which saturated solution will precipitate the greatest relative mass of solute whencooled from 70˚C to 40˚C?[1] NaCl (aq) [3] NaNO3 (aq)[2] KCl (aq) [4] KNO3 (aq)
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16.1 PROPERTIES OF SOLUTIONS
Part A Completion. Refer to section 16.1 of your textbook
A solution that holds the maximum amount of solute at a given temperature is said to
be _____(1)_______.
Two liquids that are mutually soluble in each other are called ____(2)_____.
Generally, the solubility of a solid in water _______(3)______ with increasing
temperature; gases, however, become more soluble in water when temperature
______(4)_______. The solubility of gases is also affected by changes in
_______(5)______. A solution that holds more solute than is normally possible is
called ______(6)_______.
Part B True-False
Classify each of these statements as always true (AT), sometimes true (ST) or never true (NT)
_____ (7) The rate at which a solid solute dissolves can be increased by grinding.
_____ (8) As the temperature of a solvent decreases, the solubility of a solute increases.
_____ (9) Liquids such as oil and water, which do not mix, are said to be immiscible.
_____ (10) Pressure has no effect on amount of solute that can dissolve in a certain mass of water.
Part C Matching
_____ (11) saturated solution a. the amount of a substance that dissolves in a given mass of solvent at a given temperature
_____ (12) solubility b. solution that contains the maximum amount of solute for a given mass of solvent at a constant temperature
_____ (13) supersaturated c. a solution that holds more solute than it can solution theoretically at a given temperature
_____ (14) miscible d. a solution that contains less solute than possible at a given temperature
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e. description of two liquids that dissolve in each otherExercises on Molarity and Dilution
A. Selected Response
(1) What is the molarity of a solution that contains 20. grams of CaBr2 in 0.50 liter of solution?[1] 0.50 M [3] 5.0 M[2] 0.20 M [4] 10. M
(2) What is the total number of grams of NaOH (formula mass = 40. g/mol) in 500. mL of a1.0 M solution?[1] 10. [3] 40.[2] 20. [4] 80.
(3) What is the total number of moles of solute contained in 0.50 liters of 3.0 M HCl?[1] 1.0 [3] 3.0[2] 1.5 [4] 3.5
(4) How many grams of KOH are needed to prepare 250. mL of a 2.00 M solution of KOH(formula mass = 56.0 g/mol)?[1] 1.00 [3] 28.0[2] 2.00 [4] 112
(5) What is the volume, in liters, of a 4.0 M solution that contains 205. grams of NaCl? [1] 0.88 L [3] 51 L[2] 1.1 L [4] 0.020 L
B. Constructed Response
(1) A solution containing 28.0 grams of KOH is diluted with water to 1000 mL. What is the molarity of the resulting solution?
(2) A solution of sodium carbonate, Na2CO3, contains 53.0 grams of solute in 250. mL solution. What is its molarity?
(3) A mass of 98.0 grams of sulfuric acid, H2SO4, is dissolved in water to prepare a 0.50 Msolution. What is the volume of the solution in L?
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(4) How many grams of NaCl is present in 231 mL of 6.60 M NaCl (aq)?
(5) What is the concentration of a 750 mL solution containing 50.0 grams of nitric acid,
C. Dilution Problems
(1) Calculate the molarity of the solution that results from diluting 500 mL of 2.0 M HCl (aq)to 1000 mL.
(2) Calculate the molarity of the solutions that results from diluting 200 mL of 4.0 M NaCl to800 mL.
(3) Through dilution with water, 400 mL of 0.37 M KI (aq) is prepared. If the molarity of the stock solution was 1.0 M, what volume of the stock KI (aq) was used to prepare the solution?
(4) How many mL of 12.0 M HCl (aq) would I need to prepared 300 mL of a 3.0 M HCl (aq)?
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Worksheet on Concentrations / Parts Per Million
Tier A
(1) You leave out a 1.0 M solution of NaCl (aq) overnight. As water evaporatesfrom the solution,
a. what happens to the volume of solution?
b. does the molarity of the solution change? Explain why or why not.
c. does the number of moles of NaCl change? Explain why or why not.
(2) The concentration of HF in an aqueous solution is 1500 ppm. The mass of thesolution is 50.0 grams. What is the mass of the HF?
(3) In a 15.0 gram sample of a gaseous mixture, 0.00500 grams is ozone. Whatis the concentration of ozone in ppm?
(4) The concentration of Neon gas in a gaseous mixture is 5 ppm. What is the massof a mixture which contains 14.00 grams of Neon?
(5) The mass of a sample of a CH4 / O2 mixture is 1.5 kg. If the concentration of CH4
is 20000 ppm, what is the mass of the CH4 in grams?
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Tier B
(1) You leave out a 1.0 M solution of NaCl (aq) overnight. As water evaporatesfrom the solution,
a. what happens to the volume of solution?
b. does the molarity of the solution change? Explain why or why not.
c. does the number of moles of NaCl change? Explain why or why not.
(2) The concentration of Neon gas in a gaseous mixture is 5 ppm. What is the massof a mixture which contains 14.00 grams of Neon?
(3) The mass of a sample of a CH4 / O2 mixture is 1.5 kg. If the concentration of CH4
is 20000 ppm, what is the mass of the CH4 in grams?
(4) A gaseous mixture contains 0.00200 moles of N2 (g). The concentration of N2 inthe mixture is 5.0 x 103 ppm. What is the mass, in grams, of the mixture?
(5) 3.00 kg of the mysterious substance X is dispersed in a body of water. The concentration of X is 274 parts per billion. What is the mass of the body of water in grams?
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Colligative Properties: Boiling Point Elevation and Freezing Point Depression
1. Compared to an aqueous solution, pure water will have a[1] higher freezing point and a lower boiling point.[2] higher freezing point and a higher boiling point.[3] lower freezing point and a lower boiling point.[4] lower freezing point and a higher boiling point.
2. Which solution containing 1 mole of solute dissolved in 1000 grams of water has the lowest freezing point?[1] KOH (aq) [3] CH3OH (aq)[2] C2H5OH (aq) [4] C11H22O10 (aq)?
3. Which solution has the highest boiling point temperature?[1] 1.0 M KNO3 (aq) [3] 1.0 M Ca(NO3)2 (aq)[2] 2.0 M KNO3 (aq) [4] 2.0 M Ca(NO3)2 (aq)
4. A 1.0 molar solution of MgCl2 has a higher boiling point than a 1.0 molar solution of[1] FeCl3 [3] BaCl2
[2] CaCl2 [4] NaCl
5. Consider the following 4 solutions, all of which are at a concentration of 0.5 M
A. (NH4)3PO4 (aq)B. NaC2H3O2 (aq)C. C6H12O6 (aq)D. K2CO3 (aq)
Place the 4 solutions in order from lowest to highest freezing point[1] C, B, D, A [3] C, A, B, D[2] A, D, B, C [4] D, B, A, C
6. As more solute is dissolved into an aqueous solution, it will be observed that[1] the freezing point decreases and the boiling point decreases.[2] the freezing point decreases and the boiling point increases.[3] the freezing point increases and the boiling point decreases.[4] the freezing point increases and the boiling point increases.
7. Consider the following temperature scale, where a, b and c are boiling temperatures of aqueous solutions
Assign the boiling points a, b and c to the following aqueous solutions:0.10 M KCl (aq), 0.20 KNO3 (aq) and 0.20 M BaCl2 (aq)
[1] a is 0.10 M KCl (aq), b is 0.20 M KNO3 (aq) and c is 0.20 M BaCl2 (aq)[2] a is 0.10 M KCl (aq), b is 0.20 M BaCl2 (aq) and c is 0.20 M KNO3 (aq)[3] a is 0.20 M BaCl2 (aq), b is 0.20 M KNO3 (aq) and c is 0.1 M KCl (aq)[4] a is 0.20 M KNO3 (aq), b is 0.20 M BaCl2 (aq) and c is 0.1 M KCl (aq)
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REVIEW FOR SOLUTIONS EXAM 2011
1. According to Table G, how many grams of KNO3 is needed to saturated 200 g H2O at 50oC?(a) 84 (b) 42 (c) 168 (d) 126
2. Compared to pure water at standard pressure, a 1.0 M aqueous solution at STP will have a(a) higher boiling and higher freezing points(b) higher boiling and lower freezing points(c) lower boiling and higher freezing points(d) lower boiling and lower freezing points
3. A solution contains 100 grams of a compound dissolved in 100 grams H2O at 50 oC. According to Table G, this solution could bea. supersaturated NaNO3 (aq) (c) supersaturated KNO3 (aq)(b) saturated NaNO3 (aq) (d) saturated KNO3 (aq)
4. At 50oC, 100 g of water is saturated with NH4Cl. According to Table G, what mass of NH4Cl must be added to saturate the solution at 70oC?(a) 0.10 g (b) 0.20 g (c) 10 g (d) 20 g
5. Which of the following compounds is least soluble in water? (a) Pb(C2H3O2)2 (c) KOH (b) AgNO3 (d) BaCO3
6. A true solution has all the following properties except(a) it is clear(b) a beam of light passing through it will be visible(c) it will not separate on standing(d) it will pass through a filter.
7. A saturated solution of SO2
(g) can be made more soluble by (a) raising its temperature (c) adding more solute (b) raising its pressure (d) stirring vigorously
8. A sample of NaOH (s) is dropped into a beaker of NaOH (aq). Some dissolves, but a few crystals remain at the bottom of the beaker despite thorough stirring. This solution(a) was unsaturated before and after the addition of the NaOH (s).(b) was saturated before and after the addition of the NaOH (s).(c) was unsaturated before the addition of the NaOH (s) but became saturated.(d) was saturated before the addition of the NaOH (s) but became unsaturated.
9. The air is currently estimated to be 390 ppm carbon dioxide gas. What mass of air contains 2.0 grams carbon dioxide? (a) 5100 g (b) 2500 g (c) 780 g (d) 390 g
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10. When water dissolves an ionic substance, which of the following will be observed? (a) The hydrogens of the water will be oriented towards the positive metal ion. (b) The hydrogens of the water will be oriented towards the negative metal ion. (c) The hydrogens of the water will be oriented towards the positive nonmetal ion. (d) The hydrogens of the water will be oriented towards the negative nonmetal ion
11. Which of the following will cause KI (s) to become more soluble in water? (a) an increase in pressure (c) an increase in temperature (b) a decrease in pressure (d) a decrease in temperature.
12. Which solute has the least change in solubility between 40˚C and 60oC?(a) KNO3 (b) NaNO3 (c) KCl (d) NaCl
13. What volume of 0.100 M NaOH (aq) solution contains 10.0 grams of NaOH (s)?(a) 100 L (b) 2.5 L (c) 1 L (d) 0.025 L
14. A saturated solution of KCl (aq) in 50 g H2O at 90oC cools to 10oC. What mass
crystallizes? (a) 54 g (b) 27 g (c) 24 g (d) 12 g
15. Which of the following solutions has the lowest boiling point? (a) 0.9 M KClO3 (aq) (c) 0.9 M Ba(ClO3)2 (aq) (b) 1.2 M KClO3 (aq) (d) 1.2 M Ba(ClO3)2 (aq)
16. A gas becomes less soluble in water when the temperature of the solution changes (a) from 40˚C to 20˚C, and the pressure is cut in half. (b) from 40˚C to 20˚C, and the pressure is doubled. (c) from 20˚C to 40˚C, and the pressure is cut in half. (d) from 20˚C to 40˚C, and the pressure is doubled.
17. What is the % by mass composition of solute in a saturated solution of 50.grams of NaNO3 dissolved in 60. grams of water?
18. An unsaturated solution of NH4Cl in 100 grams of water at 20˚C contains 20 grams of NH4Cl (s).
The solution is heated to 60.0 ˚C. Calculate the additional amount of NH4Cl that can dissolved in this solution.
19. Explain why NH3 (g) dissolves very well in water while O2 (g) dissolves very poorly in water. Your answer must mention both NH3 and O2.
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