What is the pH of a solution made by the addition of 0.34 mole of Na2HPO4 and 0.65 mole of NaH2PO4 and sufficient water to give a total volume of 1.2 L? The pKa of H2PO4 is 7.21.
What is the pH of a solution made by the addition of 0.34 mole of Na2HPO4...
What is the pH of the buffer that results when 14.0 g of NaH2PO4 and 7.84 g of Na2HPO4 are diluted with water to a volume of 0.940 L? (K, of H2PO4 = 6.2E-8, the molar masses of NaH2PO4 and Na2HPO4 are 120.0 g/mol and 142.0 g/mol, respectively) 0 7.21 0 7.53 0 -6.88 O 6.96 O 6.88
What is the pH of a 1.0 L buffer that is 0.10 M in Na2HPO4 and 0.15 M in NaH2PO4? Write the equilibrium reaction equation and corresponding Ka expression for the buffer. Ka for H2PO4- is 6.2 x 10^-8
a) What are the concentrations of Na2HPO4 and NaH2PO4 in a 0.30 M phosphate buffer solution pH 7.0? Use pKa 6.82 b) Describe how you would prepare 250 mL of the buffer in part (a) given that you have available to you a 1.0 M stock solution of NaH2PO4 and solid Na2HPO4(FW 141.96 g/mol). Provide your answer in milliliters of NaH2PO4 and grams of Na2HPO4. c) Suppose you use 100 ml of this buffer in an experiment and 0.003 mol...
3) Calculate the pH of a solution by mixing 50.0 mL of 0.200 M Na2HPO4 with 20.0 mL 0.0400 M NaH2PO4. (Hint: Buffer solution. Use Henderson-Hasselbalch equation) H3PO4 5 H+ + H2PO4 pkı = 2.1 H2PO4 5 H+ + HPO42- pK2 = 7.2 HPO42- 5 H+ PO43- pK3 = 12.3
22. To simulate the pH of blood, which is 7.4, a buffer solution made by dissolving sodium dihydrogen phosphate (Kg = 6.2 x 10-4) and sodium hydrogen phosphate (Kx = 3.6 x 10-13) together in an aqueous solution can be used. What mole ratio of Na2HPO4/NaH2PO4 is required to produce a solution with a pH of 7.4? A. B. C. D. E. 1.2 1.6 0.90 1.0 0.96
A) A buffer solution contains 0.373 M NaH2PO4 and 0.348 M Na2HPO4. Determine the pH change when 0.083 mol HBr is added to 1.00 L of the buffer. pH change = ___ B) A buffer solution contains 0.330 M NH4Br and 0.379 M NH3 (ammonia). Determine the pH change when 0.086 mol HClO4is added to 1.00 L of the buffer. pH after addition − pH before addition = pH change = ___
1) Solution Components A 1 mL 100 mM NaH2PO4 + 9 mL 100 mM Na2HPO4 B 5 mL 100 mM NaH2PO4 + 5 mL 100 mM Na2HPO4 C 9 mL 100 mM NaH2PO4 + 1 mL 100 mM Na2HPO4 D 10 mL 100 mM NaH2PO4 stock solution E 10 mL 100 mM Na2HPO4 stock solution F 10 mL distilled water pKa of phosphate: 6.8 How would you calculate the pH of each equation using the Henderson Hasselbalch equations? 2) Tris...
Phosphoric acid is a triproccd (K 6.9x10-3, 6.2x10-8, and Ka3 4.8x 10-13). To find the pH of a buffer composed of H2PO4 (aq) and HPO (aq), which pKa value would you use in the Henderson-Hasselbalch equation? O pK 1 = 2.16 O p 2=7.21 O pKa3 12.32 Calculate the pH of a buffer solution obtained by dissolving 11.0 g of KH2PO4(s) and 26.0 g of Na2HPO4(s) in water and then diluting to 1.00 L Number pH= | Phosphoric acid is...
Generally, common buffers have concentrations of the acid and base components that are between 0.1 M and 1.0 M. Because the acid is less concentrated, we will set its concentration to 0.100 M. What mass of the acid is required to form 1.00 L of 0.100 M solution? Target pH = 7.71 Acid/Base pair: NaH2PO4/Na2HPO4 pKa = 7.21 [Na2HPO4] > [NaH2PO4] g NaH2PO4
Goal- to make a 1L solution of phosphate buffer at pH 7.8 If you make up a 1M aqueous solution each of: NaH2PO4 and Na2HPO4 How much of each solution would you need to add (mix) to make up a 1 liter solution of 0.4 M phosphate at pH 7.8 Hint: the pKa for H2PO4- <-> HPO4 2- + H+ is 6.8)