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
The answer is given in the attachment.
a buffer with a ph of 7.5 is needed. which combination of concentrations of Nah2po4 ( ka=6.2 x10-8) and Na2HPO4 (ka=4.8 x10-13) would give a ph closest to 7.5? a) 0.1 M NaH2PO4 and 0.9 M Na2HPO4 b)1.0 M NaH2PO4 and 1.0 M Na2HPO4 c) 0.1M NaH2PO4 and 0.2 M Na2HPO4 d) 0.9 M NaH2PO4 and 0.1 M Na2HPO4
I need help with #4. "show by calculation why acetic acid (Ka = 1.8 X 10^-5), when combined with NaC2H3O3 as a buffer, will not produce a pH o 9.00" 1. What is the pH of a 1.0L buffer that is 0.10 M in Naz HPO4 and 0.15 M in NaH2PO4? Write the equilibrium reaction equation and corresponding Ka expression for the buffer. K for H2PO4 is 6.2 X 108 2. A 10.00 mL sample of 0.300 M NH3 is...
Calculate the pH of a dihydrogen phosphate/hydrogen phosphate buffer prepared with the following concentration. (Ka for H2PO4− is 6.2 × 10−8). Report your answer to three significant figures. 2.0 M NaH2PO4 and 2.0 M Na2HPO4:
You are instructed to create 200. mL of a 0.63 M phosphate buffer with a pH of 6.0. You have phosphoric acid and the sodium salts NaH2PO4, Na2HPO4, and Na3PO4 available. (Enter all numerical answers to three significant figures.) H3PO4(s) + H2O(l) equilibrium reaction arrow H3O+(aq) + H2PO4−(aq) Ka1 = 6.9 ✕ 10−3 H2PO4−(aq) + H2O(l) equilibrium reaction arrow H3O+(aq) + HPO42−(aq) Ka2 = 6.2 ✕ 10−8 HPO42−(aq) + H2O(l) equilibrium reaction arrow H3O+(aq) + PO43−(aq) Ka3 = 4.8 ✕ ...
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...
You are instructed to create 400. mL of a 0.39 M phosphate buffer with a pH of 6.2. You have phosphoric acid and the sodium salts NaH2PO4, Na2HPO4, and Na3PO4 available. (Enter all numerical answers to three significant figures.) H3PO4(s) + H2O(l) = H30+ (aq) + H2P04 (aq) Kai = 6.9 x 10-3 H2PO4 (aq) + H20(1) =H30+ (aq) + HPO42-(aq) Ka2 = 6.2 x 10-8 HPO42-(aq) + H20(I) = H30+(aq) + PO43-(aq) Ka3 = 4.8 x 10-13 Which of...
You are instructed to create 400. mL of a 0.40 M phosphate buffer with a pH of 6.4. You have phosphoric acid and the sodium salts NaH2PO4, Na2HPO4, and Na3PO4 available. (Enter all numerical answers to three significant figures.) H3PO4(s) + H2O(l) H3O+(aq) + H2PO4−(aq) Ka1 = 6.9 ✕ 10−3 H2PO4−(aq) + H2O(l) H3O+(aq) + HPO42−(aq) Ka2 = 6.2 ✕ 10−8 HPO42−(aq) + H2O(l) H3O+(aq) + PO43−(aq) Ka3 = 4.8 ✕ 10−13 Which of the available chemicals will you use...
You are instructed to create 400. mL of a 0.39 M phosphate buffer with a pH of 6.2. You have phosphoric acid and the sodium salts NaH2PO4, Na2HPO4, and Na3PO4 available. (Enter all numerical answers to three significant figures.) H3PO4(s) + H20(I) =H30+ (aq) + H2PO4 (aq) Kai = 6.9x10-3 H2PO4 (aq) + H20(1) =H30+ (aq) + HPO42-(aq) Ka2 = 6.2 x 10-8 HPO42-(aq) + H20(1) = H30+(aq) + PO43-(aq) Ka3 = 4.8x10-13 Which of the available chemicals will you...
You are instructed to create 400. mL of a 0.39 M phosphate buffer with a pH of 6.2. You have phosphoric acid and the sodium salts NaH2PO4, Na2HPO4, and Na3PO4 available. (Enter all numerical answers to three significant figures.) H3PO4(s) + H20(1) =H30+ (aq) + H2PO4 (aq) Kai = 6.9x10-3 H2PO4 (aq) + H20() = H30+(aq) + HPO42- (aq) Ka2 = 6.2x 10-8 HPO42-(aq) + H20(I) = H30+(aq) + PO43-(aq) Ka3 = 4.8 x 10-13 Which of the available chemicals...
Buffer Practice 1.) You wish to prepare 750 mL of a buffer solution of pH = 7.00 and you decide to use NaH2PO4 as the acid, K2 = 6.2 x 10. You have on hand a 0.175 M solution of this acid. Kai = 7.5 x 103, Ka2 = 6.2 x 10-8, K3 = 4.2 x 10-13 a.) Calculate the pH of the NaH2PO4 solution. b.) Calculate the grams of Na2HPO4 that need to be added to 750 mL of...