# What must be the pH of an aqueous solution of NH3 if it is 4 2 ionized Kb 1 8 1 5 chemistry homework help

hi there, i need help solving these Acid and Base Equilibrium questions. i dont want these solved for me i just need help on where to start and a general idea of how to aproach each problem. these questions seem very dissimilar to the stuff we did in class so im a little lost. any help would be awesome thanks

1. What must be the pH of an aqueous solution of NH3 if it is 4.2% ionized. Kb = 1.8 Ã— 10âˆ’5 .

2. The anti-malarial drug quinine, C20H24O2N2, is a diprotic base with a water solubility of 1.00 g per 1900 mL of solution. a. Write the equations for the ionization equilibrium corresponding to pKb1 = 6.0 and pKb2 = 9.8. b. What is the pH of saturated aqueous quinine?

3. Determine if a solution containing of sodium bicarbonate, NaHCO3, will be acidic, basic, or neutral. DO NOT calculate its pH. For carbonic acid, Ka1 = 4.4 Ã— 10âˆ’7 ; Ka2 = 4.7 Ã— 10âˆ’11 . Justify your answer.

4. You are asked to prepare a 100.0-mL sample of a solution with a pH of 5.50 by dissolving an appropriate amount of a solute in water with a pH = 7.00. How many grams of ammonium chloride are required to reach this pH?