Question

7.Calculate the amounts of the required chemicals for preparing the following acetic acid/acetate buffer solution and its pH values. Please give detail steps of your calculation and use proper significant numbers. No points will be given if only answers are given without detail and reasonable calculations (subtotal 15 pts): A. In the first step, if you are required to prepare a 2.00M sodium acetate in 200.0 mL distilled water, how many grams of sodium acetate should be added in 200 mL water? (3 pts) In the 2nd step, if 1.00M acetic acid will be added in the above solution, what will the pH value of the acetic acid/sodium buffer solution be? Assuming the change in volume will not be significant when all the chemicals are added. The dissociation value (Ka) of acetic acid is 1.78x105. (3 pts) If you plan to use the above stock solution from the 2"d step to prepare a new buffer solution in pH-4.50, what is the chemical of the above two chemicals and how many additional moles of it should be added in this 200.0 mL solution? Assuming the change in volume will not be significant and all chemicals will be dissolved in water (4 pts) B. C. D. Determine both the pOH and pH values of 0.15 M ammonia (NH3), assuming the dissociation value of ammonia is K1.8x10 (3+2-5 pts)

Answer 1

Salt 2n to tle oma

Pago No ID ehamical? kb KH 1-2, 0-5 913.2x 106

Page No. Dete 214-5-oY 8-36 s