Question

The weak acid HA is determined to be 9.14% dissociated when the initial concentration of HA...

The weak acid HA is determined to be 9.14% dissociated when the initial concentration of HA is 0.0200M. Calculate Ka for this acid.

Science   Chemistry   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

HA + H2O <===> H3O+ + A-

9.14% dissociated means

(concentration of [H3O+] / concentration of [HA]) x 100 = 9.14

(concentration of [H3O+] /0.02) x 100 = 9.14

(concentration of [H3O+] /0.02) = 9.14 / 100

(concentration of [H3O+] /0.02) = 0.0914

concentration of [H3O+] = 0.0914 x 0.02

concentration of [H3O+] = 0.00183 M

from the equation [H3O+] = [A-] = 0.00183

concentration of HA at equilibrium = 0.02 - 0.00183 = 0.01817

now wxpression of Ka

Ka = [H3O+][A-] / [HA]

Ka = [0.00183][0.00183] / [0.01817]

Ka = 1.84 x 10-4

0 0
Know the answer?
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
Similar Questions
The weak acid, HA, is 2.4% dissociated in a 0.22M Solution. Calculate (a) the Ka, (b)...
The weak acid, HA, is 2.4% dissociated in a 0.22M Solution. Calculate (a) the Ka, (b) the pH of the solution, and (c) the amount of 0.1M KOH required to neutralize 550 ml of the weak acid solution.
A solution containing a monoprotic weak acid (HA) that is 8.82% dissociated was found to have...
A solution containing a monoprotic weak acid (HA) that is 8.82% dissociated was found to have a pH of 2.91. What is the concentration of A– at equilibrium? What is the concentration of HA at equilibrium? Calculate the pKa for this acid.
A solution of a weak acid HA has initial concentration c and acid ionization constant Ka....
A solution of a weak acid HA has initial concentration c and acid ionization constant Ka. To what concentration should the acid be diluted to make [H3O+] half of what it was? Answer in terms of c and Ka.
Percent ionization for a weak acid (HA) is determined by the following formula: Percent ionization=[HA] ionized[HA]...
Percent ionization for a weak acid (HA) is determined by the following formula: Percent ionization=[HA] ionized[HA] initial×100% For strong acids, ionization is nearly complete (100%) at most concentrations. However, for weak acids, the percent ionization changes significantly with concentration. The more diluted the acid is, the greater percent ionization. A certain weak acid, HA, has a Ka value of 9.4×10?7. Part A Calculate the percent ionization of HA in a 0.10 M solution. Part B Calculate the percent ionization of...
Calculate the weak acid, HA, concentration that remains in the aqueous phase when 50.0 mL of...
Calculate the weak acid, HA, concentration that remains in the aqueous phase when 50.0 mL of 0.184 M HA at pH = 4.75 is extracted with 50 mL of toluene three times. The partition coefficient for the extraction is 5.17, favoring toluene. The Ka for HA is 8.0 x 10−4.
A 1.25 M solution of the weak acid HA is 9.2% dissociated. What is the pH...
A 1.25 M solution of the weak acid HA is 9.2% dissociated. What is the pH of the solution?
A 0.10 mol/L solution of a weak acid was found to be 4.0% dissociated. Calculate Ka....
A 0.10 mol/L solution of a weak acid was found to be 4.0% dissociated. Calculate Ka.
1. A 0.735 M solution of a weak acid is 12.5% dissociated. (a)Calculate the [H3O+], pH,...
1. A 0.735 M solution of a weak acid is 12.5% dissociated. (a)Calculate the [H3O+], pH, [OH -], and pOH of the solution. (b) calculate the ka of the acid
Benzoic acid, C6H5CO2H, is a weak acid (Ka=6.3x10^-5). Calculate the initial concentration (in M) of benzoic...
Benzoic acid, C6H5CO2H, is a weak acid (Ka=6.3x10^-5). Calculate the initial concentration (in M) of benzoic acid that is required to produce an aqueous solution of benzoic acid that has a pH of 2.54
When 2.50 g of an unknown weak acid (HA) with a molar mass of 85.0 g/mol...
When 2.50 g of an unknown weak acid (HA) with a molar mass of 85.0 g/mol is dissolved in 250.0 g of water, the freezing point of the resulting solution is -0.259 ∘C. Calculate Ka for the unknown weak acid.
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT