1. If 0.125 M solution of a weak acid has the pH of 2.79, what is the percent io

Question

1. If 0.125 M solution of a weak acid has the pH of 2.79, what is the percent ionization of this weak acid?

i got 1.3%, is this right?

2. 25.00mL of a solution of formic acid, HCOOH, was titrated with 33.45mL of a 0.1023 M solution of sodium hydroxide until the end point was reached. Calculate the pH at the equivalence point in this titration.

i couldn't figure this one out

3. For which of the reactions below does the equilibrium lie the furthest to the left?

a. H2PO4-(aq) + HF(aq) <--> H3PO4(aq) + F-(aq)

b. H2CO3(aq) + Cl-(aq) <--> HCO3-(aq) + HCl(aq)

c. HSO4-(aq) + CO3 2-(aq) <--> SO4 2-(aq) + HCO3-(aq)

d. NH4+(aq) + OH-(aq) <--> NH3(aq) + H2O(l)

e. F-(aq) + NH4+(aq) <--> HF(aq) + NH3(aq)

i got B for this one, is this correct?

4. What is the pH of 25.00mL of hypochlorous acid/ hypochlorite buffer solution, originally 0.300M in HClO and 0.400M in ClO-, after 1.50x106-3 moles of NaOH have been added to the buffer? Assume that there's no volume change due to the addition of NaOH.

i got 7.81, is this correct?

5. What compound, when added to the beaker in which the following reaction is at equilibrium, will cause the reaction to proceed in reverse? C2H5COOH(aq) + H2O(l) <--> C2H5COO-(aq) + H3O+(aq).

a. H20

b. KOH

c. KCl

d. C2H5COOH

e. C2H5COOK

i got B for this one

thanks!

Explanation / Answer

1. If 0.125 M solution of a weak acid has the pH of 2.79, what is the percent ionization of this weak acid?

% ionization = [H+] / M * 100%

M = 0.125

[H+] = 10^-pH = 10^-2.79 = 0.0016218

% ionization = 0.0016218/0.125 * 100 = 1.29744 %

which is prety proximate to 1.3%

NOTE: consider posting all other questions in another set of Q&A. We are not allowed to answer to multiple questions in a single set of Q&A

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.