Question

An analytical chemist is titrating 142.0 mL of a 0.3500 M solution of acetic acid (HCH3CO2)...

An analytical chemist is titrating 142.0 mL of a 0.3500 M solution of acetic acid (HCH3CO2) with a 1.100 M solution of KOH. the pKa of acetic acid is 4.70. Calculate the pH of the acid solution after the chemist has added 49.90 mL of the KOH solution to it. Please round your answer to 2 decimal places

Homework Answers

Answer #1

Given molarity of acetic acid=0.35 M=0.35 mol/L and volume=142 mL=0.142 L. (Since 1 L=1000 mL)

Moles of acetic acid=molarity x volume=0.35 mol/L x 0.142 L=0.0497 mol.

And molarity of KOH=1.1 M=1.1 mol/L and volume=49.90 L=0.0499 L.

Moles of KOH=1.1 mol/ L x 0.0499 L=0.05489 mol.

The neutralization reaction is

CH3COOH+KOH -----> CH3COOK + H2O.

Therefore moles of acid =moles of base or moles of H^+ =moles of OH^-.

But here moles of KOH (OH^-) are more.

Therefore moles of OH^- remaining=0.05489 mol - 0.0497 mol=0.00519 mol OH^-.

Total volume=142 mL+49.90 mL=191.9 mL=0.1019 L

Therefore [OH^-]=moles /volume=0.00519mol/0.1919 L

[OH^-]=0.027 M

Since KOH is a strong acid then pOH=-log[OH^-]=- log(0.027)

pOH=1.567

Then pH=14-pOH=14-1.567

pH=12.43.

Please let me know if you have any doubt. Thanks.

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
An analytical chemist is titrating 120.6mL of a 0.9100M solution of acetic acid HCH3CO2 with a...
An analytical chemist is titrating 120.6mL of a 0.9100M solution of acetic acid HCH3CO2 with a 0.2000M solution of KOH . The pKa of acetic acid is 4.70 . Calculate the pH of the acid solution after the chemist has added 656.0mL of the KOH solution to it. Note for advanced students: you may assume the final volume equals the initial volume of the solution plus the volume of KOH solution added. Round your answer to 2 decimal places.
An analytical chemist is titrating 138.2 mL of a 1.100 M solution of butanoic acid (HC3H7CO2)...
An analytical chemist is titrating 138.2 mL of a 1.100 M solution of butanoic acid (HC3H7CO2) with a 0.6000 M solution of KOH. The pKa of butanoic acid is 4.82. Calculate the pH of the acid solution after the chemist has added 294.3 mL of the KOH solution to it. Please round to 2 decimal places.
An analytical chemist is titrating 150.0 mL of a 0.5800 M solution of nitrous acid HNO2...
An analytical chemist is titrating 150.0 mL of a 0.5800 M solution of nitrous acid HNO2 with a 0.2800 M solution of KOH. The pKa of nitrous acid is 3.35. Calculate the pH of the acid solution after the chemist has added 320.0 mL of the 0.2800 M KOH solution to it.
An analytical chemist is titrating 81.1 mL of a 0.5900 M solution of trimethylamine ((CH3)3N) with...
An analytical chemist is titrating 81.1 mL of a 0.5900 M solution of trimethylamine ((CH3)3N) with a 0.1300 M solution of HNO3. The pKb of trimethylamine is 4.19. Calculate the pH of the base solution after the chemist has added 415.2 mL of HNO3 solution to it. Round your answer to 2 decimal places.
An analytical chemist is titrating 187.2mL of a 0.5700M solution of propylamine C3H7NH2 with a 0.4700M...
An analytical chemist is titrating 187.2mL of a 0.5700M solution of propylamine C3H7NH2 with a 0.4700M solution of HNO3 . The pKb of propylamine is 3.46 . Calculate the pH of the base solution after the chemist has added 244.6mL of the HNO3 solution to it.
A chemistry graduate student is given 450.mL of a 0.90M acetic acid HCH3CO2 solution. Acetic acid...
A chemistry graduate student is given 450.mL of a 0.90M acetic acid HCH3CO2 solution. Acetic acid is a weak acid with Ka=1.8x10^−5. What mass of KCH3CO2 should the student dissolve in the HCH3CO2 solution to turn it into a buffer with pH =4.35? You may assume that the volume of the solution doesn't change when the KCH3CO2 is dissolved in it. Be sure your answer has a unit symbol, and round it to 2 significant digits.
A buffer solution is prepared by mixing 78.9 mL of 0.0419 M acetic acid with 35.9...
A buffer solution is prepared by mixing 78.9 mL of 0.0419 M acetic acid with 35.9 mL of 0.0317 M sodium acetate. A table of pKa values can be found here. 1. Calculate the pH (to two decimal places) of this solution. Assume the 5% approximation is valid and that the volumes are additive. 2. Calculate the pH (to two decimal places) of the buffer solution after the addition of 1.88 g of sodium acetate (NaCH3COO) to the buffer solution...
Calculate the pH of a solution of 4.0 mL of 6.0 M Acetic acid, 46.0 mL...
Calculate the pH of a solution of 4.0 mL of 6.0 M Acetic acid, 46.0 mL water and 3.3 grams of Sodium acetate trihydrate before and after 1.0 mL of 3 M NaOH is added to the solution.        Ka of HAc = 1.8 x 10 -5 Please Use ICE method thank you
A 25.0 mL sample of a 0.115 M solution of acetic acid is titrated with a...
A 25.0 mL sample of a 0.115 M solution of acetic acid is titrated with a 0.144 M solution of NaOH. Calculate the pH of the titration mixture after 10.0, 20.0, and 30.0 mL of base have been added. (The Ka for acetic acid is 1.76 x 10^-5). 10.0 mL of base = 20.0 mL of base = 30.0 mL of base =
You are titrating 50.00 mL of a 0.161 M formic acid solution with 0.2949 M sodium...
You are titrating 50.00 mL of a 0.161 M formic acid solution with 0.2949 M sodium hydroxide. Calculate the pH of the solution after adding 46.94 mL of titrant.
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT