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Chemistry 120 Exam 1 Name __________________September 25, 2006

SHOW YOUR WORK. NO WORK, NO CREDIT INCLUDE LABELS AND PROPER NUMBER OF SIG FIGS

Up to 75% of the credit for a problem will be given for correctly setting it up, including labels on all numbers.

CONSTANTS AND EQUATIONS YOU MAY NEED

I PLEDGE ON MY HONOR THAT DURING THE EXAM I HAVE NEITHER GIVEN NOR RECEIVED ASSISTANCE NORHAVE I SEEN ANY DISHONEST WORK.

Signed __________________________________________________________________________If you feel you can’t sign this, contact the instructor (e-mail or in person)

Multiple choice - circle the correct answer.1. (2 pt) What symbol (metric system prefix) is used to represent the factor 10-6?

a) n b) µ c) M d) m

2. (2 pt) Which of the following elements has chemical properties similar to nitrogen?

a) boron (B) b) silicon (Si) c) phosphorus (P) d) sulfur (S)

3. (2 pt) Which of the following elements is a liquid at room temperature?

a) helium b) sodium c) bromine d) chlorine

4. (2 pt) All of the following elements are nonmetals except

a) hydrogen b) carbon c) arsenic d) oxygen

5. (2 pt) How many significant figures are there in the answer for the following problem? 23.1 + 0.5588 + 17 = ?

a) 1 b) 2 c) 3 d) 4

6. (2 pt) If hitting the bull’s eye is the desired result, the figure on the right represents

a) poor accuracy and poor precision. b) poor accuracy and good precision.

c) good accuracy and poor precision. d) good accuracy and good precision.

7. (2 pt) Radium (88Ra) belongs to which group of the periodic table?

a) alkaline earth metals b) halogens c) alkali metals d) noble gases

8. (2 pt) Which of the following numbers has the greatest number of significant figures?

a) 418000 b) 0.5070 c) 6.02 x 1023 d) 0.000201

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9. (2 pt) Identify the chemical symbol of element Q in .1940Q

a) Sc b) K c) Ca d) this element doesn’t exist

10. (2 pt) Which statement about diluted solutions is false? When a solution is diluted

a) the molarity of the solution decreases. b) the number of moles of solute remains unchanged.

c) the number of moles of solvent remains unchanged. d) the concentration of the solution decreases.

11. (2 pt) Which one of the following compounds contains the smallest percent chlorine by mass?

a) Cl2 b) HCl c) MgCl2 d) AuCl3

12. (2 pt) What group of elements does the shaded area in the following periodic table indicate?

a) alkali metals b) alkaline earth metals

c) halogens d) transition metals

13. (2 pt) Cherry Kool-Aid is an example of

a) a heterogeneous mixture b) a compound

c) an element d) a homogeneous mixture

14. (2 pt) To the correct number of significant figures, what is the temperature reading on the following Celsius thermometer?

___________________________

15. (3 pts) What is the oxidation number (charge) on Cr in Na2CrO4? Explain your reasoning.

16. (2 pts) If VO3-3 is called vanadate, what is the formula for pervanadate?

17. (3 pts) Write the formula of the compound that results when UO2+2 combines with IO4

-1.

18. (3 pts each) Name the following compounds.

a. N2O ________________________________

b. Zn(NO2)2 ________________________________

19. (3 pts each) Write the formula for each of the following compounds.

a. copper (I) sulfite ________________________________

b. calcium nitride ________________________________

20. (8 pts) The following diagram represents the reaction of A2 (small, unshaded spheres) with B (large,shaded spheres). How many moles of product can be produced from the reaction of 1.0 moles of A2 and1.0 moles of B? Explain your reasoning.

21. (8 pts) A piece of metal ore weighs 9.00 g. When placed into a graduated cylinder containing water, theliquid level rises from 21.25 mL to 26.47 mL. What is the density of the ore?

22. (6 pts) Why is it NOT a good idea to store coats and bookbags on the lab benches in lab?

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23. (8 pts) One type of cordless phone operates on a frequency of 800 MHz. What is the wavelength of this radiation?

24. (8 pts) A typical C-Cl bond requires 330 kJ/mole of energy to break the bond. What frequency of light has photons with just enoughenergy to break this bond?

25. Lead chloride reacts with phosphoric acid in aqueous solution by the following reaction:

Pb(NO3)2 + H3PO4 ! Pb3(PO4)2 + HNO3

a. (6 pts) Balance the reaction.

b. (8 pts) The Pb3(PO4)2 is not soluble in the water, so it can be recovered by filtration. In an experiment a student mixed 50.00 mLof 0.1000 M H3PO4 with an excess of Pb(NO3)2 and recovered 1.3x10-3 moles of solid Pb3(PO4)2, what is the percent yield for thisreaction?

Chemistry 120 Exam 2 Name __________________October 16, 2006

SHOW YOUR WORK. NO WORK, NO CREDIT INCLUDE LABELS AND PROPER NUMBER OF SIG FIGS

Up to 75% of the credit for a problem will be given for correctly setting it up, including labels on all numbers.

CONSTANTS AND EQUATIONS YOU MAY NEED

AX2 linear AX5 trigonal bipyramid AX6 octahedralAX3 trigonal planar AX4E see saw AX5E square pyramidAX2E bent AX3E2 T AX4E2 square planarAX4 tetrahedral AX2E3 linear AX3E3 TAX3E trigonal pyramid AX2E4 linearAX2E2 bent

I PLEDGE ON MY HONOR THAT DURING THE EXAM I HAVE NEITHER GIVEN NOR RECEIVED ASSISTANCE NORHAVE I SEEN ANY DISHONEST WORK.

Signed __________________________________________________________________________If you feel you can’t sign this, contact the instructor (e-mail or in person)

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Circle the correct answer:

1. (2 pts) Reaction of A (unshaded spheres) with B2 (shaded spheres) is shown schematically in the following diagram. Which equationbest describes the stoichiometry of the reaction?

a) 16 A + 4 B2 ! 8 A2B b) 4 A + B2 ! A4B2 c) 4 A + B2 ! 8 A2B d) 4 A + 2 B ! 4 A4B2

2. (2 pts) Which element has the ground-state electron configuration [Kr]5s2 4d7

a) 27Co b) 45Rh c) 43Tc d) 64Gd

3. (2 pts) An element that has the valence electron configuration 3s2 3p4 belongs to which period and group?

a) period 3 group 3 b) period 6 group 3 c) period 3 group 4 d) period 3 group 6

4. (2 pts) How many electrons can a single orbital hold?

a) 2l + 1 b) 2 c) 8 d) 2n

5. (2 pts) Which block of elements, represents the f-block elements?

a) A (crosshatch) b) B (X’ed) c) C (shaded) d) D (chickenwire)

6. (2 pts) What compound is formed when 3Li + 35Br2 are mixed.

a) LiBr b) LiBr2 c) Li2Br3 d) LiBr3

7. (2 pts) Which of the atoms below has the lowest ionization energy?

a) 13Al b) 17Cl c) 50Sn d) 53I

8. (2 pts) The spheres in the figure represent atoms of Li, Be, B, and F (notnecessarily in that order). Which one of these spheres represents an atom of B?

a) sphere (a) b) sphere (b) c) sphere (c) d) sphere (d)

9. (2 pts) Which of the following are allowed resonance forms of NCS-1?

a) I b) II c) III d) I and III

AC

B

D

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NH

Cl ClCOO

Xe FF

FF H

Se H

10. (2 pts) What is the H-N-H bond angle in NH3 (Lewis Structureshown)?

a) 90° b) 109.5° c) 120° d) 180°

11. (2 pts) What is the shape of a molecule that is an sp3 hybrid with one lone pair of electrons around the central atom?

a) linear b) trigonal planar c) trigonal pyramid d) bent

12. (2 pts each) Name the following compounds.

a. SO2 ________________________________

b. HgSO4 ________________________________

13. (2 pts each) Write the formula for each of the following compounds.

a. ammonium perchlorate ________________________________

b. arsenic (III) sulfide ________________________________

14. (3 pts) Which is the smallest ion P-3, S-2, Cl-1? Explain your reasoning.

a) P-3 b) S-2 c) Cl-1 d) all the same size

15. (6 pts) What is the formal charge on the oxygen in the resonance form of SOCl2 shown.

16. (6 pts each) Draw Lewis structures, including any resonance forms, for NO2-1 and XeF2.

17. (1 pt each) Fill in the blanks for each structure

Molecular Shape _______________________

Polar (yes/no)? _______________________Molecular Shape _______________________

Polar (yes/no)? _______________________

Molecular Shape _______________________

Polar (yes/no)? _______________________

Molecular Shape _______________________

Polar (yes/no)? _______________________

18. (6 pts) Label the following binary compounds as ionic, polar covalent, or purely covalent. Then explain your reasoning.

NO ______________ LiI ______________ N2 ______________

19. (8 pts) Write the electron configuration for 80Hg. You may start with an inert gas core if you wish.

HNHH

OS ClCl

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20. (8 pts) The electron configuration for 44Ru is [Kr] 5s2 4d6. Is +1 expected to be a stable charge for Ru? Explain your reasoning.

21. (5 pts) Which Lewis Structure below cannot exist as a real molecule? Explain your reasoning.

22. (6 pts) While working in the lab you accidentally drop a 250 mL reagent bottle of 6 M NaOH and it shatters on the floor. You makea quick check of yourself and find no evidence of splashes or cuts. What should you do next?

23. (8 pts) An isotopically enriched sample of oxygen is 80.00% 16O (atomic mass 15.943 amu) and 20.00% 18O (atomic mass17.986 amu). What is the average atomic mass of oxygen in this sample?

Chemistry 120 Exam 3 Name __________________November 6, 2005

SHOW YOUR WORK. NO WORK, NO CREDIT INCLUDE LABELS AND PROPER NUMBER OF SIG FIGS

Up to 75% of the credit for a problem will be given for correctly setting it up, including labels on all numbers.

IONS Soluble/Insoluble ExceptionsGroup I metals and NH4

+ soluble noneNitrates, Acetates, Perchlorates soluble noneFluoride soluble Group IIChlorides, Bromides, and Iodides soluble silver, lead, mercury(I)Sulfates soluble strontium, barium, leadOther anions insoluble Group I and ammonium salts,

Group II sulfides, barium oxide & hydroxide,strontium oxide & hydroxide

IBr

Br

BrCl

Br

Br

Br FBr

Br

Br

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AX2 AY2 AZ2

AX2 linear AX5 trigonal bipyramid AX6 octahedralAX3 trigonal planar AX4E see saw AX5E square pyramidAX2E bent AX3E2 T AX4E2 square planarAX4 tetrahedral AX2E3 linear AX3E3 TAX3E trigonal pyramid AX2E4 linearAX2E2 bent

Enthalpies of Formation (∆Hf) for Selected SpeciesC10H22 (l) -59.67 kJ/mole HC2H3O2 (l) -484.5 kJ/mole CO (g) -110.5 kJ/moleC3H8 (g) -105 kJ/mole H2O (g) -241.8 kJ/mole CO2 (aq) -413.8 kJ/moleC6H6 (l) +49.0 kJ/mole H2O (l) -285.8 kJ/mole CO2 (g) -393.5 kJ/moleC6H12O6 -1260 kJ/mole H2O2 (l) -187.8 kJ/mole O (g) +249.2 kJ/moleCH3OH (l) -238.7 kJ/mole NH3 (g) -46.1 kJ/mole O2 (g) 0 kJ/moleC2H5OH (l) -277.7 kJ/mole NH3 (aq) -80.3 kJ/mole O3 (g) +143 kJ/mole

I PLEDGE ON MY HONOR THAT DURING THE EXAM I HAVE NEITHER GIVEN NORRECEIVED ASSISTANCE NOR HAVE I SEEN ANY DISHONEST WORK.

Signed __________________________________________________________________________If you feel you can’t sign this, contact the instructor (e-mail or in person)

1. (2 pts) What volume of a 0.500 M NaOH solution contains 0.0125 mole of NaOH?

a) 0.00625 L b) 0.025 L c) 0.006250 L d) 0.0250 L

2. (2 pts) Strontium phosphate reacts with sulfuric acid to form strontium sulfate and phosphoric acid. What is the coefficientfor sulfuric acid when the equation is balanced using the lowest, whole-numbered coefficients?

a) 1 b) 3 c) 2 d) none of these

3. (2 pts) If the percent yield for the following reaction is 65.0%, how many moles of KClO3 are needed to actually collect 6.00moles of O2?

2 KClO3 ! 2 KCl + 3 O2

a) 6.00 * 0.650 * (3/2) moles KClO3 b) (6.00/0.650) * (3/2) moles KClO3

c) 6.00 * 0.650 * (2/3) moles KClO3 d) (6.00/0.65) * (2/3) moles KClO3

4. (2 pts) Three different substances, AX2, AY2, and AZ2, weredissolved in water in separate beakers with the results shown in thediagram. (Water molecules are omitted for clarity.) Which of thesubstances is the strongest electrolyte?

a) AX2 b) AY2 c) AZ2 d) all the same

5. (2 pts) Predict the products of a reaction between Ba(NO3)2 (aq) and K2SO4 (aq).

a) BaSO3 (s) and KNO2 (aq) b) BaSO4 (s) and KNO3 (aq)

c) BaSO4 (aq) and KNO3 (aq) d) Ba(SO4)2 (s) and K2NO3 (aq)

6. (2 pts) The reaction of HNO3 + KOH ! KNO3 + H2O is best classified as a(n)

a) precipitation reaction b) acid base reaction c) redox reaction d) synthesis reaction

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7. (2 pts) If the concentration of Na+1 ions (black spheres) in the funnelis 0.120 M and the volumes in the funnel and flask are the same,what is the molarity of the I3

-1 (grey spheres) in the flask?(Oppositely charged ions in each container are omitted for clarity).

a) 4.00 M b) 0.120 M c) 0.0400 M d) 0.360 M

8. (2 pts) What reagent could be used to separate Cl-1 from C2H3O2-1

when added to an aqueous solution containing both?

a) NaI (aq) b) AgNO3 (aq) c) CuSO4 (aq) d) Ba(OH)2 (aq)

9. (2 pts) Which of the following compounds is insoluble in water?

a) CaCO3 b) NaNO2 c) H2SO3 d) ZnCl2

10. (2 pts) What is the balanced net ionic equation for the reaction of AgNO3 (aq) with Cu (s).

a) Ag+1 (aq) + Cu (s) ! Ag (s) + Cu+2 (aq) b) 2 AgNO3 (aq) + Cu (s) ! 2 Ag (s) + Cu(NO3)2 (aq)

c) AgNO3 (aq) + Cu (s) ! Ag (s) + CuNO3 (aq) d) 2 Ag+1 (aq) + Cu (s) ! 2 Ag (s) + Cu+2 (aq)

11. (2 pts) What is the change in oxidation number (charge) for the chromium in the following unbalanced reduction halfreaction?

Cr2O7-2 + H+ ! Cr+2 + H2O

a) 6 b) 4 c) 5 d) 8

12. (2 pts) HBr, HI, HNO3, NaBr, and KNO3 are all classified as

a) strong acids b) strong bases c) strong electrolytes d) weak electrolytes

13. (2 pts) At constant pressure, the exothermic combustion of 0.1667 mole of C2H6 (g) releases 259 kJ of heat. What is ∆H forthe reaction (below)?

2 C2H6 + 7 O2 ! 4 CO2 + 6 H2O

a) -1554 kJ/mole C2H6 b) + 1554 kJ/mole C2H6 c) + 259 kJ d) -259 kJ

14. (2 pts) You have a sample of gas in a cylinder with a moveablepiston as shown in diagram (1). The initial pressure, number ofmoles, and temperature of the gas are noted on the diagram. Whichdiagram (2)-(4) most closely represents the position of the pistonwhen the pressure and the number of moles of gas are both doubledwhile keeping the temperature constant?

a) diagram (2) b) diagram (3) c) diagram (4) d) none

15. (2 pts) Which of the following compounds is a weak base?

a) NH3 b) H2SO4 c) Na2O d) CH3Cl

16. (2 pts) Which metal is the best heat conductor (specific heat inparentheses)?

a) Al (0.90 J/g·deg) b) Cu (0.39 J/g·deg) c) Pb (0.16 J/g·deg) d) Sn (0.222 J/g·deg)

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17. (2 pts each) Name the following compounds.

a. HNO2 ________________________________

b. SnI4 ________________________________

c. HF ________________________________

18. (2 pts each) Write the formula for each of the following compounds.

a. hydrosulfuric acid ________________________________

b. arsenic (V) hydride ________________________________

c. carbonic acid ________________________________

19. (8 pts) What is the total pressure in a 10.0 L flask which contains 0.288 mol of N2 (g) at 20.0°C?

20. (9 pts) Balance the following redox reaction that takes place in acidic solution.

ClO4-1 + NH4

+1 ! Cl-1 + N2

21. (9 pts) Write and balance the net ionic equation.

HNO3 + K2SO3 ! KNO3 + H2SO3

22. (6 pts) In lab the class is running a series of reactions that use several potentially hazardous chemicals. Groups are workingon the lab benches and are scattered throughout the lab (typical situation for our lab). Your group has finished theexperiment earlier than those groups around you. Is it OK for your group to remove your safety goggles to work oncalculations at your lab desk while the others finish the lab? Explain your reasoning.

23. (9 pts) Calculate the ∆H for the reaction below using the ∆Hf values on the front page.

3 C3H8 (g) + 10 O3 (g) ! 9 CO2 (g) + 12 H2O (g)

24. (8 pts) When 0.0153 mole of KNO3 is dissolved in 100.0 g of H2O, 533.8 J of heat is absorbed from the surroundings. Whatis the enthalpy of solution (∆Hsoln) for KNO3?

25. (7 pts) The ∆H for a particular reaction is 18.3 kJ/mole and the ∆S is 50.0 J/mole·K. Is the reaction spontaneous at 300K?Explain your reasoning.

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Chemistry 120 Exam 4 Name __________________November 29, 2006

SHOW YOUR WORK. NO WORK, NO CREDIT

INCLUDE LABELS AND PROPER NUMBER OF SIG FIGS Up to 75% of the credit for a problem will be given for correctly setting it up, including labels on all numbers.

IONS Soluble/Insoluble ExceptionsGroup I metals and NH4

+ soluble noneNitrates, Acetates, Perchlorates soluble noneFluoride soluble Group IIChlorides, Bromides, and Iodides soluble silver, lead, mercury(I)Sulfates soluble strontium, barium, leadOther anions insoluble Group I and ammonium salts,

Group II sulfides, barium oxide & hydroxide,strontium oxide & hydroxide

AX2 linear AX5 trigonal bipyramid AX6 octahedralAX3 trigonal planar AX4E see saw AX5E square pyramidAX2E bent AX3E2 T AX4E2 square planarAX4 tetrahedral AX2E3 linear AX3E3 TAX3E trigonal pyramid AX2E4 linearAX2E2 bent

Enthalpies of Formation (∆Hf) for Selected SpeciesC10H22 (l) -59.67 kJ/mole HC2H3O2 (l) -484.5 kJ/mole CO (g) -110.5 kJ/moleC3H8 (g) -105 kJ/mole H2O (g) -241.8 kJ/mole CO2 (aq) -413.8 kJ/moleC6H6 (l) +49.0 kJ/mole H2O (l) -285.8 kJ/mole CO2 (g) -393.5 kJ/moleC6H12O6 -1260 kJ/mole H2O2 (l) -187.8 kJ/mole O (g) +249.2 kJ/moleCH3OH (l) -238.7 kJ/mole NH3 (g) -46.1 kJ/mole O2 (g) 0 kJ/moleC2H5OH (l) -277.7 kJ/mole NH3 (aq) -80.3 kJ/mole O3 (g) +143 kJ/mole

I PLEDGE ON MY HONOR THAT DURING THE EXAM I HAVE NEITHER GIVEN NORRECEIVED ASSISTANCE NOR HAVE I SEEN ANY DISHONEST WORK.

Signed __________________________________________________________________________If you feel you can’t sign this, contact the instructor (e-mail or in person)

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1. (2 pts) Which figure best indicates the direction of the dipole moment in acetone, (CH3)2C=O?

2. (2 pts) In pure liquid methanthiol, CH3SH, which intermolecular forces are present?

a) Dipole-dipole and ion-dipole forces are present.b) Dispersion, hydrogen bonding and dipole-dipole forces are present.c) Only hydrogen bonding forces are present. d) Dispersion and dipole-dipole forces are present.

3. (2 pts) Which of the following has the largest dipole moment?

a) KCl b) H-H c) O=C=O d) CH3F

4. (2 pts) Which of the following compounds exhibits hydrogen bonding?

a) CH3F b) H2S c) H3C-O-CH3 d) CH3CH2NH3

5. (2 pts) Which compound has the lowest boiling point?

a) CH3CH2OH b) CH3CH2CH3 c) H3C-O-CH3 d) CH3CH2NH3

6. (2 pts) Which should be least soluble in water?

a) b)

c) d)

7. (2 pts) One reason ionic compounds do not dissolve well in nonpolar solvents is that

a) not all cations and anions have the same magnitude of charge and therefore do not form neutral ion pairs.b) ion-dipole interactions are too large for effective solvation to occur.c) ion-solvent interactions are not strong enough to solvate the ions in solution.d) there are no forces of attraction between ions and nonpolar molecules.

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8. (2 pts) Which of the intermolecular forces is the most important contributor to the high surface tension shown by water?

a) dipole-dipole forces b) ion-dipole forces c) hydrogen bonding d) dispersion forces

9. (2 pts) Molecules of a liquid can pass into the vapor phase only if the

a) liquid has little surface tension.b) vapor pressure of the liquid is high.c) temperature of the liquid is near its boiling point.d) molecules have sufficient kinetic energy to overcome the intermolecular forces in the liquid.

10. (2 pts) What is the equilibrium constant expression (Ka) for the acid dissociation of nitrous acid HNO2?

a) Ka = ([H3O+1][NO2-1])/([HNO2]) b) Ka = ([H3O+1][NO2

-1])/([HNO2][H2O])

c) Ka =([HNO2][H2O])/([H3O+1][NO2-1]) d) Ka = ([HNO2])/([H3O+1][NO2

-1])

11. (2 pts) Picture (1) represents the equilibrium mixture for the endothermic reaction A + B W 2 AB at 298 K. Which picturerepresents the equilibrium mixture at 400 K?

a) (2) b) (3) c) (4) d) none of them

12. (2 pts) In an experiment to study the equilibrium shown below, known amounts of H2, N2, and NH3 were added to a sealedflask and the mixture allowed to come to equilibrium. At the end of the experiment it was found that the amount of NH3had increased. Which statement is true about this experiment?

3 H2 (g) + N2 (g) W 2 NH3 (g)

a) Keq = Q b) Keq > Q c) Keq < Q d) More information is needed to make a statement about Keq.

13. (2 pts) Which compound is acidic?

a) NaC2H3O2 b) NaCl, c) NH4Cl d) C2H6

14. (2 pts) Of these weak acids, which is the strongest?

a) HF with Ka = 3.5 x 10-4 b) HC2H3O2 with Ka = 1.8 x 10-5

c) HC7H5O2 with Ka = 6.5 x 10-5 d) HClO with Ka = 3.5 x 10-8

15. (2 pts) What is the hydronium ion concentration of an acid rain sample that has a pH of 3.35?

a) 2.24 x 10-11 M b) 0.525 M c) 3.35 M d) 4.47 x 10-4 M

16. (2 pts) Which one of the following can behave either as a Brønsted-Lowry acid or base in an aqueous solution?

a) H3PO4 b) HI c) HSO3-1 d) NH3

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17. (2 pts) What statement is most consistent for an acid with a pH = 3?

a) It is twice as strong as an acid with a pH of 6.b) It is half a strong as an acid with a pH = 6c) It is one thousandth as strong an acid with a pH of 6.d) It is one thousand times as strong as an acid with a pH = 6.

18. (3 pts each) Name the following compounds.

a. H3PO2 ________________________________

b. NO2 ________________________________

19. (3 pts each) Write the formula for each of the following compounds.

a. potassium dichromate ________________________________

b. bromous acid ________________________________

20. Consider the equilibrium mixture: Pb(ClO)2 (s) + 2 H2O (l) W Pb+2 (aq) + 2HClO (aq) + 2 OH-1 (aq)

a. (10 pts) Write the equilibrium constant expression for the following reaction

Keq =

b. (9 pts) If a few drops of 0.3 M Pb(NO3)2 were added to 1 mL of the equilibrium mixture in a test tube, would the amountof precipitate (reactant) increase, decrease, or stay the same? Explain your reasoning.

21. (5 pts) During a particular lab you are heating a solution with a bunsen burner. Someone working across the desk from youpushes their book bag out of their road. In a few moments you notice that it has gotten too close to your burner and isburning brightly. If you are in our lab (GSC 243), where would you find a fire extinguisher?

22. (10 pts) An aqueous solution is 17.75% sulfuric acid, H2SO4. If the density of the solution is 1.1094 g/mL, what is themolarity?

23. (10 pts) What is the pH of a 0.020 M Ba(OH)2 solution?

24. (10 pts) Calculate the pH for 0.500 M HCN (Ka = 4.9 x 10-10)?