Question

In: Chemistry

A buffer solution is prepared from equal volumes of 0.200 M acetic acid and 0.600 M...

A buffer solution is prepared from equal volumes of 0.200 M acetic acid and 0.600 M sodium acetate use 1.80 *10^-5 as Ka for acetic acid.

a.) what is the pH of the solution

b.) Is the solution acidic or basic

c.) What is the pH of a solution that results when 3.00ml of 0.034 M HCl is added to 0.200L of the original buffer

Solutions

Expert Solution

PKa   = -logKa

           = -log(1.8*10^-5)

             = 4.75

PH   = PKa + log[CH3COONa]/[CH3COOH]

       = 4.75 + log0.6/0.2

       = 4.75 + 0.477

       = 5.227

b. PH = 5.227

The solution is acidic

c.

no of moles of CH3COONa = molarity *volume in L

                                         = 0.6*0.2   = 0.12moles

no of moles of CH3COOH = molarity *volume in L

                                        = 0.2*0.2   = 0.04moles

no of moles of HCl   = molarity * volume in L

                              = 0.034*0.003   = 0.000102moles

no of moles of CH2COONa after addition o f0.000102moles of HCl   = 0.12-0.000102   = 0.119898moles

no of moles of CH2COOH after addition o f 0.000102moles of HCl    = 0.04+0.000102   = 0.040102moles

PH   = PKa + log[CH3COONa]/[CH3COOH]

       = 4.75 + log0.119898/0.040102

       = 4.75 + 0.4756

       = 5.2256 >>>>answer


Related Solutions

A buffer solution that is 0.10 M sodium acetate and 0.20 M acetic acid is prepared....
A buffer solution that is 0.10 M sodium acetate and 0.20 M acetic acid is prepared. Calculate the initial pH of this solution. The Ka for CH3COOH is 1.8 x 10-5 M. As usual, report pH to 2 decimal places. A buffered solution resists a change in pH. Calculate the pH when 21.1 mL of 0.031 M HCl is added to 100.0 mL of the above buffer.
A buffer solution was prepared by mixing 516.9 mL of 0.25 M acetic acid and 103.8...
A buffer solution was prepared by mixing 516.9 mL of 0.25 M acetic acid and 103.8 mL of 0.89 M sodium acetate. Calculate the pH of the solution given that Ka is 1.8 x 10—5 . Answer in 2 decimal places.
A buffer solution was prepared by mixing 300.0 mL of a 0.200 M solution of hydroxylamine...
A buffer solution was prepared by mixing 300.0 mL of a 0.200 M solution of hydroxylamine (OHNH2, Kb = 1.1 × 10-8) and 250.0 mL of a 0.300 M solution of its hydrochloride salt (OHNH3+ Cl- ). Calculate the pH of the solution after the addition of 1.08 g of solid NaOH (molar mass = 40.00 g/mol). Assume that there is no volume change upon the addition of solid.
A buffer solution was prepared by mixing 300.0 mL of a 0.200 M solution of hydroxylamine...
A buffer solution was prepared by mixing 300.0 mL of a 0.200 M solution of hydroxylamine (OHNH2, Kb = 1.1 × 10-8) and 250.0 mL of a 0.300 M solution of its hydrochloride salt (OHNH3+ Cl- ). Calculate the pH of the solution after the addition of 1.08 g of solid NaOH (molar mass = 40.00 g/mol). Assume that there is no volume change upon the addition of solid. A. 8.22    B. 5.55 C. 6.30 D. 5.78
A buffer solution is prepared by mixing 20.0 mL 0.45 M HAc (acetic acid) with 35.0...
A buffer solution is prepared by mixing 20.0 mL 0.45 M HAc (acetic acid) with 35.0 mL 0.45 MNaAc (sodium acetate) (a) What is the amount of 4.0 M HAc which must be added to this buffer solution to double [H3O+]? (b) What is the amount of 2.0 M HCl that must be added to decrease the pH by 0.50? (c) How much NaOH(s) in g has to be added to the solution to raise the pH by 2.00?
A 25.0-mL solution of 0.100 M acetic acid is titrated with a 0.200 M KOH solution....
A 25.0-mL solution of 0.100 M acetic acid is titrated with a 0.200 M KOH solution. Calculate the pH after the following additions of the KOH solution: a) 0.0 mL b) 5.0 mL c) 10.0 mL d) 12.5 mL e) 15.0 mL
A buffer solution is prepared by mixing 35mL of 0.18M CHCOOH (acetic acid) and 25mL of...
A buffer solution is prepared by mixing 35mL of 0.18M CHCOOH (acetic acid) and 25mL of 0.23M NaCH3COO (sodium acetate). Fine the change in pH when 5.0 mL of 0.12M HCl is added. Been stuck on this one for a while. If you can show step by step that would help so much!
PART A) A solution is prepared by mixing equal volumes of 0.17 M HCl and 0.42...
PART A) A solution is prepared by mixing equal volumes of 0.17 M HCl and 0.42 M HNO3. (Assume that volumes are additive.) Express the pH to two decimal places. PART B) Using the chart Estimate [H3O+] in a 1.5 M solution of each acid. Express the molar concentrations to two significant figures separated by commas. I'm stuck on the one that says very large. For all the other ones I multiplied the Ka by the 1.5M. The answer for...
Calculate the pH of a buffer solution prepared by mixing 20 mL of 5.0% acetic acid...
Calculate the pH of a buffer solution prepared by mixing 20 mL of 5.0% acetic acid with 20 mL of 0.50 M NaOH and 100 mL of water
A 280.0 mL buffer solution is 0.250 M in acetic acid and 0.250 M in sodium...
A 280.0 mL buffer solution is 0.250 M in acetic acid and 0.250 M in sodium acetate. For acetic acid, Ka=1.8×10−5. Part A)  What is the initial pH of this solution? Part B)  What is the pH after addition of 0.0150 mol of HCl? Part C)  What is the pH after addition of 0.0150 mol of NaOH?
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT