You are asked to prepare 500. mL of a 0.300 M acetate buffer at pH 4.90...

You are asked to prepare 500. mL of a 0.300 M acetate buffer at pH 4.90 using only pure acetic acid (MW=60.05 g/mol, pKa=4.76), 3.00 M NaOH, and water. Answer the following questions regarding the preparation of the buffer.

What volume of 3.00 M NaOH must you add to the acetic acid to achieve a buffer with a pH of 4.90 at a final volume of 500 mL? (Ignore activity coefficients.)

Solutions

Expert Solution

PH = PKa + log[NaAc]/[HAc]

4.9 = 4.76 + log[NaAc]/[HAc]

log[NaAc]/[HAc] = 4.9-4.76

log[NaAc]/[HAc] = 0.14

[NaAc]/[HAc] = 10^0.14

[NaAc]/[HAc] = 1.38

[NaAc] = 1.38[HAc]

no of moles of acetic acid (HAc) = molarity * volume in L

= 0.3*0.5 = 0.15moles

total no of moles in buffer = 0.15moles

[NaAc]+[HAc] = 0.15

1.38[HAc]+[HAc] = 0.15

2.38[HAc] = 0.15

[HAc] = 0.15/2.38

[HAc] = 0.063moles

[NaAC] = 0.15-0.063 = 0.087moles

NaOH react with HAc to gives NaAC 0.087 moles of NaOH is needed

no of moles of NaOH = 0.087 moles

molarity of NaOH = no of moles/volume in L

3 = 0.087/volume in L

volume in L = 0.087/3 = 0.029L = 29ml

queen_honey_blossom answered 1 year ago

Next > < Previous

Related Solutions

You are asked to prepare 500. mL of a 0.150 M acetate buffer at pH 4.90...

You are asked to prepare 500. mL of a 0.150 M acetate buffer at pH 4.90 using only pure acetic acid (MW=60.05 g/mol, pKa=4.76), 3.00 M NaOH, and water. Answer the following questions regarding the preparation of the buffer. 2. What volume of 3.00 M NaOH must you add to the acetic acid to achieve a buffer with a pH of 4.90 at a final volume of 500 mL? (Ignore activity coefficients.) Answer is not 14.5

You are asked to prepare 500. mL of a 0.250 M acetate buffer at pH 4.90...

You are asked to prepare 500. mL of a 0.250 M acetate buffer at pH 4.90 using only pure acetic acid (MW=60.05 g/mol, pKa=4.76), 3.00 M NaOH, and water. Answer the following questions regarding the preparation of the buffer. 1. How many grams of acetic acid will you need to prepare the 500 mL buffer? Note that the given concentration of acetate refers to the concentration of all acetate species in solution. 2. What volume of 3.00 M NaOH must...

You are asked to prepare 500. mL of a 0.200 M acetate buffer at pH 5.10...

You are asked to prepare 500. mL of a 0.200 M acetate buffer at pH 5.10 using only pure acetic acid (MW=60.05 g/mol, pKa=4.76), 3.00 M NaOH, and water. Answer the following questions regarding the preparation of the buffer. What volume of 3.00 M NaOH must you add to the acetic acid to achieve a buffer with a pH of 5.10 at a final volume of 500 mL?

Show how would you prepare a solution of 500 ml of a 0.15 M acetate buffer....

Show how would you prepare a solution of 500 ml of a 0.15 M acetate buffer. You have available the following: 6M HCl, 4 M acetic, solid sodium acetate, solid sodium hydroxide

Suppose 50.00 mL of 0.300 M HCl is added to an acetate buffer prepared by dissolving...

Suppose 50.00 mL of 0.300 M HCl is added to an acetate buffer prepared by dissolving 0.100 mol of acetic acid and 0.110 mol of sodium acetate in 0.100 L of solution. What are the initial and final pH values? What would be the pH if the same amount of HCl solution were added to 170 mL of pure water?

a)Using a 0.15 M Acetate buffer with a pH of 4.9, you add 0.75 mL of...

a)Using a 0.15 M Acetate buffer with a pH of 4.9, you add 0.75 mL of 0.08 M HCl to 73 mL of the buffer. What is the new pH of the solution? (Enter your answer to three significant figures.) b) Using a 0.15 M Acetate buffer with a pH of 4.9, you add 0.75 mL of 0.08 M NaOH to 73 mL of the buffer. What is the new pH of the solution? (Enter your answer to three significant...

You need to prepare an acetate buffer of pH 5.50 from a 0.899 M acetic acid...

You need to prepare an acetate buffer of pH 5.50 from a 0.899 M acetic acid solution and a 2.73 M KOH solution. If you have 775 mL of the acetic acid solution, how many milliliters of the KOH solution do you need to add to make a buffer of pH 5.50? The pKa of acetic acid is 4.76.

You need to prepare an acetate buffer of pH 5.54 from a 0.805 M acetic acid...

You need to prepare an acetate buffer of pH 5.54 from a 0.805 M acetic acid solution and a 2.64 M KOH solution. If you have 475 mL of the acetic acid solution, how many milliliters of the KOH solution do you need to add to make a buffer of pH 5.54? The pKa of acetic acid is 4.76.

You need to prepare an acetate buffer of pH 5.67 from a 0.841 M acetic acid...

You need to prepare an acetate buffer of pH 5.67 from a 0.841 M acetic acid solution and a 2.94 M KOH solution. If you have 675 mL of the acetic acid solution, how many milliliters of the KOH solution do you need to add to make a buffer of pH 5.67? The pKa of acetic acid is 4.76.

You need to prepare an acetate buffer of pH 5.83 from a 0.853 M acetic acid...

You need to prepare an acetate buffer of pH 5.83 from a 0.853 M acetic acid solution and a 2.61 M KOH solution. If you have 825 mL of the acetic acid solution, how many milliliters of the KOH solution do you need to add to make a buffer of pH 5.83? The pKa of acetic acid is 4.76.

Subjects