calculate the ph after the addition of 100.0 mL of 1.0M HCL to a 500 ml...

Question

Question

calculate the ph after the addition of 100.0 mL of 1.0M HCL to a 500 ml buffer made up of 0.500M HF (ka=6.8x10^-4) & 0.500 M NaF?

science chemistry

Answer 1

Answer #1

initially

millimoles of HF = 0.500 x 500 = 250

millimoles of NaF = 0.500 x 500 = 250

millimoles of HCl added = 1.0 x 100 = 100

after HCl added

millimoles of HF = 250 + 100 = 350

millimoles of NaF = 250 - 100 = 150

total volume = 100 + 500 = 600 mL

[HF] = 350 / 600 = 0.583 M

[NaF] = 150 / 600 = 0.25 M

mixture of HF and NaF act as acidic buffer

pH = pKa + log [NaF] / [HF]

pKa = - log Ka = - log 6.8 x 10^-4 = 3.17

pH = 3.17 + log [0.25] / [0.583]

pH = 2.80

Add a comment

Answer 2

Similar Homework Help Questions

Calculate the pH after adding 15.0 mL of 0.10 M HCl to 100.0 mL of the...

Calculate the pH after adding 15.0 mL of 0.10 M HCl to 100.0 mL of the the previous buffer. Use an ICE table with each column of the first row having a value. Previous buffer: 0.150 M Na2HPO4/0.250 M Na2HPO4 pKa = 6.86 pH= 7.08
Calculate the pH of a solution formed by mixing 100.0 mL of 0.100 M NaF and...

Calculate the pH of a solution formed by mixing 100.0 mL of 0.100 M NaF and 100.0 mL of 0.040 M HCI. Ka of HF = 7.24 x 10-4. A 3.32 B.3.54 C.3.14 D.2.74 E 2.96
a buffer solution consisting of 30ml of 1.0M HC2H3O2 + 30 ml 1.0M NaC2H3O2. 1. Write...

a buffer solution consisting of 30ml of 1.0M HC2H3O2 + 30 ml 1.0M NaC2H3O2. 1. Write the chemical equation for buffer solution 2. Calculate ph of buffer solution and account for dilution 3. Calculate ph for buffer solution with addition of 2mL of 1.0 M HCL and account for dilution. 4. Calculate pH for buffer solution with added 2mL of 1.0 M NaOH And account for dilution. The Ka of HC2H3O2 is 1.8 x 10^-5

1a. A buffer solution is prepared by mixing 15.0 mL of 2.00 M Acetic Acid and...

1a. A buffer solution is prepared by mixing 15.0 mL of 2.00 M Acetic Acid and 10.0 mL of 1.50 M NaC2H3O2. Determine the pH of the solution after the addition of 0.01 moles NaOH (assume there is no change in volume when the NaOH is added). Ka HC2H3O2 = 1.80E-5 1b. A buffer solution is prepared by mixing 55.0 mL of 1.15 M HF and 99.0 mL of 0.450 M NaF. Determine the pH of the solution after the...
Calculate the hypothetical pH AFTER addition of 15.00 mL of reagent for the titration of 50.00...

Calculate the hypothetical pH AFTER addition of 15.00 mL of reagent for the titration of 50.00 mL of 0.0800 M NaOH with 0.1000 M HCl at 25°C. QUESTION 7 10 poir Calculate the hypothetical pH AFTER addition of 40.00 mL of reagent for the titration of 50.00 mL of 0.0800 M NaOH with 0.1000 M HCl at 25°C. Calculate the hypothetical pH AFTER addition of 46.00 mL of reagent for the titration of 50.00 mL of 0.0800 M NaOH with...
Determine the pH at the half-equivalent point during the titration of 100.0 ml of 0.484 M...

Determine the pH at the half-equivalent point during the titration of 100.0 ml of 0.484 M HF with 50.0 ml of 0.484 M NaOH. Ka = 6.8x10-4

Calculate the following: a. The pH of a 500.0 mL buffer solution containing 0.75 M HCN...

Calculate the following: a. The pH of a 500.0 mL buffer solution containing 0.75 M HCN (Ka = 6.2 x 10^-10) and 0.55 M NaCN b. The pH of the above buffer after the addition of 100.0 mL of 1.0 M NaOH. c. The pH of the buffer if 100.0 mL of 1.0 M HCl was added to the solution in part a.
Calculate the pH of the acetate buffer after 4 mL of 0.100 M HCl has been...

Calculate the pH of the acetate buffer after 4 mL of 0.100 M HCl has been added. Acetate buffer is made with 0.160 M NaC2H3O2 & 0.200 M HC2H3O2. We also took 10 mL of acetate buffer and diluted with 30mL of distilled water at the beginning. Ka of HC2H3O2 is 1.8 x 10^-5. I tried doing the SRF table and the pH I got was higher than the pH at the beginning so I know I am doing something...
Calculate the pH of 100.0 mL of a buffer that is 0.0800 M NH4Cl and 0.100 M NH 3 before and after the addition of 1.00...

Calculate the pH of 100.0 mL of a buffer that is 0.0800 M NH4Cl and 0.100 M NH 3 before and after the addition of 1.00 mL of 5.25 M HNO3- 1st attempt Part 1 (0.5 point) M See Periodic Table See = pH before Part 2 (0.5 point) = pH after

How many moles of HCl need to be added to 200.0 mL of a 0.200 M solution of NaF to make a buffer with a pH of 3.60?...

How many moles of HCl need to be added to 200.0 mL of a 0.200 M solution of NaF to make a buffer with a pH of 3.60? (Ka for HF is 6.8 x 10-4)