Question
please explain the steps please
5. Determine the Ky for CN at 25°C. The K, for HCN is 4.9 x 10-10. 6. Determine the Ka of an acid whose 0.294 M solution has
0 0
Add a comment Improve this question Transcribed image text
Answer #1

5)

Given:

Ka = 4.9*10^-10

use:

Kb = Kw/Ka

Kw is dissociation constant of water whose value is 1.0*10^-14 at 25 oC

Kb = (1.0*10^-14)/Ka

Kb = (1.0*10^-14)/4.9*10^-10

Kb = 2.041*10^-5

Answer: 2.0*10^-5

6)

use:

pH = -log [H+]

2.8 = -log [H+]

[H+] = 1.585*10^-3 M

HA dissociates as:

HA -----> H+ + A-

0.294 0 0

0.294-x x x

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

Ka = x*x/(c-x)

Ka = 1.585*10^-3*1.585*10^-3/(0.294-1.585*10^-3)

Ka = 8.59*10^-6

Answer: 8.59*10^-6

Only 1 question at a time please

Add a comment
Know the answer?
Add Answer to:
please explain the steps please 5. Determine the Ky for CN at 25°C. The K, for...
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. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions
  • CHM2046L: General Chemistry and Oualitative Analysis II; Fall 2019 Equilibrium: Determination of Acid Ionization Constant (Ka)...

    CHM2046L: General Chemistry and Oualitative Analysis II; Fall 2019 Equilibrium: Determination of Acid Ionization Constant (Ka) of a Weak Acid) (Post-lab # 8: Due Thursday 10-31", 2019) Last name First Name 1. Determine the pH of a 0.023 M HNO3 solution. 2. Calculate the concentration of H30 in a solution that contains 5.5 x 10-5 MOH at 25°C. Identify the solution as acidic, basic, or neutral. 3. Determine the [H30°) in a 0.265 M HCIO solution. The K, of HCIO...

  • TABLE 15.5 Acid lonization Constants (K) for Some Monoprotic Weak Acids at 25 °C Acid Formula...

    TABLE 15.5 Acid lonization Constants (K) for Some Monoprotic Weak Acids at 25 °C Acid Formula Structural Formula lonization Reaction К. pk, = -log (2) Chlorous acid HCIO H-0-C=0 1.1 x 10-2 1.96 Stronger acids Nitrous acid HNOZ H-O-NO 5.6 x 10-4 HCIO2(aq) + H2011) = H30* (aq) + CO2 (aq) HNO2(aq) + H20(I) = H30+ (aq) + NO2 (aq) HF(aq) + H20(1) = H30* (aq) + F"(aq) 3.25 Hydrofluoric acid HF H-F 6.3 x 10-4 3.20 O Methanoic acid...

  • TABLE 15.5 Acid lonization Constants (K) for Some Monoprotic Weak Acids at 25 °C Acid Formula...

    TABLE 15.5 Acid lonization Constants (K) for Some Monoprotic Weak Acids at 25 °C Acid Formula Structural Formula lonization Reaction К. pk, = -log (2) Chlorous acid HCIO H-0-C=0 1.1 x 10-2 1.96 Stronger acids Nitrous acid HNOZ H-O-NO 5.6 x 10-4 HCIO2(aq) + H2011) = H30* (aq) + CO2 (aq) HNO2(aq) + H20(I) = H30+ (aq) + NO2 (aq) HF(aq) + H20(1) = H30* (aq) + F"(aq) 3.25 Hydrofluoric acid HF H-F 6.3 x 10-4 3.20 O Methanoic acid...

  • Question 1 7.5 pts Determine the Ka of a weak monoprotic acid with an initial concentration...

    Question 1 7.5 pts Determine the Ka of a weak monoprotic acid with an initial concentration of 0.294 M and has a pH of 2.80 once equilibrium is reached. O 1.2* 10.5 8.6 x 106 O 4.9 × 107 0 5.4× 103 2.7

  • a) b) c) d) If the Kb of a weak acid is 2.9 10*, the K,...

    a) b) c) d) If the Kb of a weak acid is 2.9 10*, the K, of its conjugate acid must be which of the following? 2.9.10 6.46 7.54 3.4 10- The hydronium ion concentration of a 0.50 mol/L solution of hydrocyanic acid, HCN(aq), is 1.4 x 10-5 mol/L. Use Weak Acid Info 16.1 to answer the following question. The Ka for hydrocyanic acid is: 3.9 x 10-10 1.4 x 10-5 5.0 x 10-2 6.2 x 10-10 An acetic acid-sodium...

  • please explain. thanks 5. Find the pH and fraction of dissociation for a 0.0SF solution of...

    please explain. thanks 5. Find the pH and fraction of dissociation for a 0.0SF solution of the weak monoprotic acid HA whose Ka=1.4 x 106. Find the equilibrium molar concentrations of HA, A', H20 and OH, all species, for the solution. Make simplyfing assumptions to avoid solving a quadratic equation State rational for these assumptions

  • CHM2046L: General Chemistry and Qualitative Analysis II; Fall 2019 Lab # 9: EQUILIBRIUM: Calculating pH and...

    CHM2046L: General Chemistry and Qualitative Analysis II; Fall 2019 Lab # 9: EQUILIBRIUM: Calculating pH and Buffer Capacity Post-lab # 9: ( Due Monday, November 7t, 2019) Last name First Name 1. Define buffer capacity. 2. Determine the Kb for CN at 25°C. The Ka for HCN is 4.9 x 10-10, 3. Determine the [H30] in a 0.265 M HCIO solution. The Ka of HCIO is 2.9 x 10-8 rco 4. Determine the pH of a 0.461 M C6H5CO2H M...

  • 24A) 40mL of 0.2 M formic acid is titrated with a strong base (NaOH= 0.5 M). Determine the pH before any base has been...

    24A) 40mL of 0.2 M formic acid is titrated with a strong base (NaOH= 0.5 M). Determine the pH before any base has been added. Please show steps and please explain why the answer is what it is. 24B) The 40mL 0.2 M formic acid is titrated with a 6.0mL of strong base. Here NaOH can be treated as a conjugate base and formic acid is the acid. please show steps and explain! Us (24-25, Acid/base, aqueous equilibrium) 24A) (4...

  • The original given concentration was 25.0mL of 0.100 M HCO2H (formic acid Ka= 1.8x10^-4) with 0.100...

    The original given concentration was 25.0mL of 0.100 M HCO2H (formic acid Ka= 1.8x10^-4) with 0.100 M of NaOH. f) pH after adding 25.0 mL NaOH (Equivalence point). At this point 0.00250" ist 00250 mol of OH have been added, and therefore all the acid (HCO2H) has been converted into its conjugale the table below. 25.0 mL x L/1000 mL = 0.025 L 0.025 L x 0.1 mol/L = 0.0025 mol of NaOH added n converted into its conjugate base...

  • 4. 16.55 Calculate the pH of an aqueous solution at 25°C that is 0.095 M in...

    4. 16.55 Calculate the pH of an aqueous solution at 25°C that is 0.095 M in hydrocyanic acid (HCN). (K for hydrocyanic acid=4.9 x 1010 Answers TOmTzctu. 10. 16.61 Calculate the Ka of a weak acid if a 0.19-M aqueous solution of the acid has a pH of 4.52 at 25°C Answers 2. 16.71 The pH of a 0.30-M solution of a weak base is 10.66 at 25°C. What is the K of the base? Answers 4. 16.73 Calculate 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
ADVERTISEMENT