ChE 413 OFA (Only Final Assignment)

ChE 413 OFA (Only Final Assignment)December 3, 2014

1. The cathode, center and anode chambers of an electrolytic cell contain each 10 milliequivalents of HCl in an aqueous solution. What will be the number of milliequivalents of HCl in each compartment after the passage of 5 milliequivalents of electricity through the cell? Assume that t+ is 0.80 and that H2 is given off at the cathode and Cl2 at the anode.GIVEN:

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2. For propionic acid Ka = 1.34 x 10-5 at 25C. find for 0.01 molar solution of the acid (a) the degree of dissociation, (b) the hydrogen ion concentration, and (c) the pH of the solution.GIVEN:

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3. An aqueous solution at 25C is 0.01 molar in propionic acid and 0.02 molar in sodium propionate. Find for this solution (a) the degree of dissociation of the acid, (b) the hydrogen ion concentration, and (c) the pH.GIVEN:

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4. A solution at 25C contains 0.01 molar propionic acid and 0.03 molar hydrochloric acid. Find for this solution (a) the degree of dissociation of the weak acid, (b) the hydrogen ion concentration, and (c) the pH.GIVEN:

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5. A solution is composed of 0.05 molar benzoic acid and 0.10 molar sodium benzoate gives a pH of 4.50 at 25C. Find the ionization constant of the acid.GIVEN:

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6. Calculate the pH and pOH of each of the following solutions at 25C: (a) 0.001 molar H2SO4; (b) 0.001 molar NaHSO4 and (c) 0.01 molar NH4OH.GIVEN:

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7. Calculate the [H+], [H3PO4], [H2PO4-], [HPO4-2] and [PO3] in a 0.10 molar H3PO4 solution at 25C.GIVEN:

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8. If the final volume is to be 1 liter, how many moles of HCl will have to be added to 500 cc of 0.1 molar Na2CO3 in order to adjust the pH to 10.0?GIVEN:

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9. Give the formula of the acids conjugate to (a) methyl alcohol, (b) aniline, (c) dimethyl ether and the bases conjugate to (a) methyl alcohol and (b) phenolGIVEN:

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10. Calculate the hydrolytic constants (Kh) for each of the following salts at 25C: (a) urea hydrochloride, (b) ammonium carbonate, (c) disodium acid phosphate and (d) sodium bicarbonate.GIVEN:

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11. Calculate the degree of hydrolysis and [OH-] at 25C in (a) a 0.50 molar KCN solution and (b) a 0.01 molar Na2CO3 solution.GIVEN:

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12. Assuming the degree of hydrolysis to be the same for both ions, calculate the extent to which a 0.10 molar solution of aniline acetate, C6H5NH3C2H3O2 will hydrolyze at 25C. what will be the pH of the solution?GIVEN:

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13. Formulate the equilibrium constant for each of the following equilibria:a. b. c. GIVEN:

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14. For the reaction , the following data have been obtained at 25C:Equilibrium Concentration (moles/liter)

0.02330.02350.0275

0.07040.06920.0821

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15. For the reaction the equilibrium constant at 25C is 4.0 x 10-19. Calculate the silver ion concentration in a solution which was originally 0.10 molar KCN and 0.03 molar AgNO3.GIVEN:

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16. The solubility of CaF2 in water at 18C is 2.04 x 10-4 mol/L. calculate (a) the solubility product and (b) the solubility in 0.01 molar NaF solution. GIVEN:

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17. Calculate the solubility of PbI2 in (a) pure water, (b) 0.04 molar KI, and (c) 0.04 molar Pb(NO3)2 at 25C.GIVEN:

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18. The solubility product of CaF2 at 18C is 3.4 x 10-11 while that of CaCO3 is 9.5 x 10-9. What will be the nature of the first precipitate when a solution of CaCl2 is added to a solution which is 0.05 molar in NaF and 0.02 molar and 0.02 molar in Na2CO3? In a 0.02 molar solution of NA2CO3 what is the minimum concentration of NaF at which CaF2 and CaCO3 will precipitate?GIVEN:

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19. The solubility product of PbI2 is 7.47 x 10-9 at 15C and 1.39 x 10-9 at 25C. Calculate (a) the molar heat of solution of PbI2 and (b) the solubility in mole/L.GIVEN:

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Accomplished by: MERCADO, Judith Anne S.Instructor: Engr. Ray Limuel C. Laureano, ChE19