pH of buffer acidic bufferis given by, pH = pka + log(conjugate base/acid)
pKa of Formic acid = 3.74
pH = 3.74 +log(0.10/0.15)
= 3.56
NaCHO2 component of the buffer must be added to change the pH from 3.56 to 3.91
Let x be mmoles of NaCHO2 added, then
pH of buffer = pka + pka + log(conjugate base+x/acid)
3.91= 3.74 + log((25+x)/37.5)
Number of mmoles of X(NaCHO2) must be added = 30.47
mass of X(NaCHO2) must be added = 30.47*68/1000 = 2.072 gms
a 250.0 ml buffer solution initially contains 0.15 M HCHO2 and 0.10 M NaCHO2. what is...
A buffer solution is to be formed using HCHO2 and NaCHO2. Ka for HCHO2 is 1.77 x 10-4. a. Find the mass of NaCHO2 that must be dissolved in 250. mL of 1.40 M of HCHO2 to prepare a buffer solution with pH = 3.36. b. What will be the pH of the solution following the addition of 15.0 mL of 0.0100 M NaOH?
Consider the following two buffers: (i) 10.0 mL of a buffer that contains 0.10 M HClO and 0.10 M NaClO (ii) 10.0mL of a buffer that contains 0.050 M HClO and 0.10 M NaClO b.) 8 drops of 1.0 M NaOH (aq) is added to each of these buffers. 1.)Give the balanced net-ionic equation for the reaction that occurs when the NaOH (aq) is added. 2.)For which buffer (i or ii) does the pH change the greatest amount when the...
Part A a solution that is 0.20 M in HCHO2 and 0.15 M in NaCHO2 Part B a solution that is 0.11 M in NH3 and 0.22 M in NH4Cl
Suppose a buffer solution is made from formic acid, HCHO2, and sodium formate, NaCHO2. What is the net ionic equation for the reaction that occurs when a small amount of sodium hydroxide is added to the buffer? Select one: a. H3O+(aq) + OH–(aq) → 2H2O(l) b. OH–(aq) + HCHO2(aq) → CHO2–(aq) + H2O(l) c. NaOH(aq) + H3O+(aq) → Na+(aq) + 2H2O(l) d. NaOH(aq) + HCHO2(aq) → NaCHO2(aq) + H2O(l)
1.) A buffer solution contains 0.267 M acetic acid and 0.348 M potassium acetate. If 0.0285 moles of hydrochloric acid are added to 125 mL of this buffer, what is the pH of the resulting solution ? (Assume that the volume change does not change upon adding hydrochloric acid) 2.) A buffer solution contains 0.334 M hydrocyanic acid and 0.226 M potassium cyanide . If 0.0144 moles of sodium hydroxide are added to 125 mL of this buffer, what is...
A) A buffer solution contains 0.336 M KHSO3 and 0.447 M Na2SO3. If 0.0144 moles of hydroiodic acid are added to 125 mL of this buffer, what is the pH of the resulting solution ? (Assume that the volume change does not change upon adding hydroiodic acid) pH = B) If 0.0335 moles of perchloric acid are added to 250 mL of this buffer, what is the pH of the resulting solution ? (Assume that the volume change does not...
1. A buffer solution contains 0.256 M hydrofluoric acid and 0.308 M potassium fluoride. If 0.0414 moles of hydrochloric acid are added to 225 mL of this buffer, what is the pH of the resulting solution ? (Assume that the volume does not change upon adding hydrochloric acid) pH = 2. A buffer solution contains 0.328 M ammonium chloride and 0.331 M ammonia. If 0.0396 moles of sodium hydroxide are added to 225 mL of this buffer, what is the...
4. What is the pH of a 100.0 mL buffer solution containing 0.15 M NaHCO3 and 0.15 M Na2CO3? 5. What is the pH after adding 15.0 mL of 0.10 M NaOH to the solution in question 4?
A buffer solution contains 0.229 M ammonium chloride and 0.457 M ammonia. If 0.0568 moles of hydroiodic acid are added to 250 mL of this buffer, what is the pH of the resulting solution ? (Assume that the volume does not change upon adding hydroiodic acid) pH = Submit Answer Retry Entire Group 9 more group attempts remaining A buffer solution contains 0.443 M ammonium chloride and 0.314 M ammonia. If 0.0313 moles of potassium hydroxide are added to 225...
A buffer with a pH of 3.92 contains 0.19 M of sodium benzoate and 0.36 M of benzoic acid. What is the concentration of [H3O+] in the solution after the addition of 0.054 mol HCl to a final volume of 1.7 L? Assume that any contribution of HCl to the volume is negligible. [H3O+] = M Allerede C., Calculate the change in pH when 7.00 mL of 0.100 M HCl(aq) is added to 100.0 mL of a buffer solution that...