Tear Off This Top Page (Pg

Tear off the top pages (pg. 1 - 3)It is Your reference tables and scratch paper Ka TABLE, ACID-IONIZATION CONSTANTS AT 25°C*

Substance Formula Ka HC H O Acetic acid5-5 2 3 2 1.7 X 10-53 HC H O Benzoic acid5-53 7 5 5 6.3 X 10-53 5 Boric acid5-53 H3BO3 5.9 X 10-103 5-53 H2CO3 -73 Carbonic acid 33 4.3 X 10 - -113 HCO3 4.8 X 10 Cyanic acid5 HOCN5 -43 3.5 X 10 33 5 5 3 Formic acid HCHO2 1.7 X 10-4 5 3 Hydrocyanic acid HCN 4.9 X 10-103

Hydrofluoric acid HF 6.8 X 10-4

Hydrogen sulfate ion5 - -23 HSO4 1.1 X 10 5 H S Hydrogen sulfide 2 8.9 X 10-83

HS- 1.2 X 10-13† 5 Hypochlorous acid HClO 3.5 X 10-83 5 HNO Nitrous acid 2 4.5 X 10-43

Oxalic acid5 5-53 -23 H2C2O4 5.6 X 10 - -53 HC2O4 5.1 X 10 Phosphoric acid5 5-53 3 -33 H3PO4 3 3 6.9 X 10 -5 -83 H2PO4 6.2 X 10 2- -133 HPO4 4.8 X 10 Phosphorous acid 5-5 -23 H3PO3 1.6 X 10 - -73 H2PO3 7 X 10 5 5 Propionoic acid HC3H5O2 1.3 X 10-53 Pyruvic acid5 5-53 -4 HC3H3O3 1.4 X 10 Sulfurous acid 5-53 -23 H2SO3 1.3 X 10 -5 -83 HSO3 6.3 X 10

Kb table Page 1 DISSOCIATION CONSTANTS FOR BASES Dissocaiation -5Base Formula Constants at 25°C -5 -5 -5 -5 -5 Ammonia 8 NH3 41.76 X 10 -5 -5 -5 -10 Anniline 8 C6H5NH2 43.94 X 10 -5 -5 -5 -4 1-Butylamine 8 CH3(CH2) 2CH2NH2 44.0 X 10 -5 -5 -5 -4 Dimethylamine 8 (CH3) 2NH 45.9 X 10 -5 -5 -5 -5 Ethanolamine 8 HOC2H4NH2 43.18 X 10 -5 -5 -5 -4 Ethylamine 8 CH3CH2NH2 44.28 X 10 -5 -5 -5 -5 Ethylenediamine NH2C2H4NH2 4K = 8.5 X 10 -5 -5 -8 88 4K = 7.1 X 10 -5Hydrazine-5 -5H NNH -6 8 2 2 41.3 X 10 -5Hydroxlamine-5 -5HONH -8 8 2 41.07 X 10 -5Methylamine-5 -5CH NH -4 8 3 2 44.8 X 10 -5Piperidine-5 -5C H N -3 8 5 11 41.3 X 10 -5Pyridine-5 -5C H N -9 8 5 5 41.7 X 10 -5Trimethyl amine-5 -5 (CH ) N -5 8 3 3 46.25 X 10

CHEM. 111

CLS EXAM IV NAME______last first ______THERE ARE 5 PAGES TO THIS EXAM (including the cover page) Significant Figures must be correct. All set-ups must be shown (27 points) 1. Calculate the pH of the following: a. 0.500 M H 2CO3

ANSWER______3.33______

b. 0.0325 moles of NaHC2O4 is added to 100.0 mL of 2.00 M H2C2O4

ANSWER______0.46______a. 0.400 M potassium phosphate

ANSWER______12.96______Page 3 -26 (10 points) 2. Calculate the solubility of Ca3(PO4)2 in water (Ksp = 1 x 10 ) .

ANSWER______2 x 10-6______

(13 points) 3. Calculate the pH of a solution if 200.0 mL of .250M H2SO4 is added to 200.0 mL of 0.500 M methylamine.

ANSWER______5.64______

(13 points) 4. Calculate the pH of the resulting solution when 35.00 mL of 0.200M NaOH is added to 70.00 mL of 0.200 M NaH2PO4

ANSWER______7.20______(13 points) 5. Calculate the number of moles of HCl needed to be added to 2.00 L of 0.2500M pyridine to make a buffer with a pH of 8.00.

ANSWER______8.48 x 10-4 moles HCl______

(10 points) 6. 25.0 mL of 0.00100 M Na2SO4 is added to a solution containing 100.0 mL of 0.0020 M CaCl2 Will a precipitate form? You must show calculations to justify your answer. -5 Ksp of CaSO4 = 2.4 x 10

ANSWER______No ppt will form______(15 points) 7. Will the following solutions be acidic, basic or neutral? Write the equilibrium equations (and calculations, if necessary) to justify your answer.

a. NaHSO3

Acidic

b. Al(NO3)3 Acidic

c. CH3CH2NH3NO2

Acidic