HomeworkLib
Question

What is the pH of a buffer that was prepared by adding 3.96 g of sodium...

What is the pH of a buffer that was prepared by adding 3.96 g of sodium benzoate, NaC7H5O2, to 1.00 L of 0.0100 M benzoic acid, HC7H5O2? Assume that there is no change in volume. The K a for benzoic acid is 6.3 × 10–5.

science   chemistry   
0 0
Add a comment Improve this question Transcribed image text
Next > < Previous
Sort answers by oldest

Homework Answers

Answer #1

pKa = -log Ka = -log(6.3*10^-5) = 4.2

moles of sodium benzoate = 3.96 gm/144.11g/mol = 0.0275 mol

moles of benzoic acid = 1L * 0.01M = 0.01 moles

pH = pKa + Log[benzoate/benzoic acid]

     = 4.2 + log [0.0275/0.01] = 4.64

ph of the solution is 4.64

0 0
Add a comment
Know the answer?
Add Answer to:
What is the pH of a buffer that was prepared by adding 3.96 g of sodium...
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for? Ask your own homework help question. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions

  • A buffer solution contains 0.41 mol of benzoic acid (HC7H5O2) and 0.43 mol of sodium benzoate...

    A buffer solution contains 0.41 mol of benzoic acid (HC7H5O2) and 0.43 mol of sodium benzoate (NaC7H5O2) in 2.50 L. The Ka of benzoic acid (HC7H5O2) is Ka = 6.3e-05. (a) What is the pH of this buffer? pH = (b) What is the pH of the buffer after the addition of 0.16 mol of NaOH? (assume no volume change) pH = (c) What is the pH of the original buffer after the addition of 0.05 mol of HI? (assume...

  • A buffer solution is prepared by dissolving 1.49 g each of benzoic acid, C6H3CO2H, and sodium...

    A buffer solution is prepared by dissolving 1.49 g each of benzoic acid, C6H3CO2H, and sodium benzoate, NaC6H; CO2, in 150.0 mL of solution. ( Ka for benzoic acid is 6.3 x 10-5.) a. What is the pH of this buffer solution? pH = b. Which buffer component must be added, and in what quantity, to change the pH to 4.00? e must be added. Quantity = c. What quantity of 2.0 M NaOH or 2.0 M HCI must be...

  • Calculate the pH of a buffer solution that results from combining 37.5 mL of a 0.450...

    Calculate the pH of a buffer solution that results from combining 37.5 mL of a 0.450 M in benzoic acid (HC7H5O2) and 82.5 mL of a 0.250 M in sodium benzoate (NaC7H5O2). For benzoic acid, Ka = 6.5 × 10–5 .

  • What is the pH of a 0.0100 M solution of sodium benzoate, NaC7H302? (K for benzoic...

    What is the pH of a 0.0100 M solution of sodium benzoate, NaC7H302? (K for benzoic acid, HC7H502 - 6.3 x 10-5). CyH5O2 (aq) + H20(1) = HC7H5O2(aq) + OH(aq) O pH = 9.82 O pH - 0.38 O pH = 5.91 O pH = 8.10 O pH = 13.62

  • 3. A buffer is prepared by adding 45,0 mL of 0.15 M sodium benzo Benzoic acid. What is the pH of the final solution...

    3. A buffer is prepared by adding 45,0 mL of 0.15 M sodium benzo Benzoic acid. What is the pH of the final solution? by adding 45.0 mL of 0.15 M sodium benzoate to 25.0 mL of 0.1 MM

  • A buffer solution with pH 5 is to be prepared by adding sodium acetate and acetic...

    A buffer solution with pH 5 is to be prepared by adding sodium acetate and acetic acid to enough water to make 1.00 L of solution. The pKa of acetic acid is 4.75. Given 0.600 mol of sodium acetate, what amount of acetic acid should be added to produce 1.00 L of a buffer solution at pH = 5.00?

  • A buffer solution was prepared by adding 4.72 g of sodium acetate, NaCH, CO2, to 2.50...

    A buffer solution was prepared by adding 4.72 g of sodium acetate, NaCH, CO2, to 2.50 10 mL of 0.100 M acetic acid, CH3CO,H (K, = 1.8 x 10-6). a What is the pH of the buffer? pH = 5.10 Correct Find the pH using the Henderson-Hasselbalch equation: 4.72 g 1 mol NaCH, CO2 CH,CO2- ] = [NaCH,CO2] = 0.250 L -= 0.230 M 82.03 g [CH, CO2- pH = pK,+ logo = -log(1.8 x 10-5) + log CH, CO2H]...

  • A buffer with a pH of 4.33 contains 0.27 M of sodium benzoate and 0.20 M...

    A buffer with a pH of 4.33 contains 0.27 M of sodium benzoate and 0.20 M of benzoic acid. What is the concentration of [H+] in the solution after the addition of 0.056 mol of HCl to a final volume of 1.3 L? Assume that any contribution of HCl to the volume is negligible. [H+] = ? -------- A buffer with a pH of 4.09 contains 0.17 M of sodium benzoate and 0.22 M of benzoic acid. What is the...

  • Part A: What is the pH of a buffer prepared by adding 0.708 mol of the...

    Part A: What is the pH of a buffer prepared by adding 0.708 mol of the weak acid HA to 0.406 mol of NaA in 2.00 L of solution? The dissociation constant Ka of HA is 5.66×10−7. Part B:What is the pH after 0.150 mol of HCl is added to the buffer from Part A? Assume no volume change on the addition of the acid. Part C: What is the pH after 0.195 mol of NaOH is added to the...

  • PART A: What is the pH of a buffer prepared by adding 0.809 mol of the...

    PART A: What is the pH of a buffer prepared by adding 0.809 mol of the weak acid HA to 0.507 mol of NaA in 2.00 L of solution? The dissociation constant Ka of HA is 5.66×10−7. PART B: What is the pH after 0.150 mol of HCl is added to the buffer from Part A? Assume no volume change on the addition of the acid. PART C:What is the pH after 0.195 mol of NaOH is added to the...

ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT