1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
AysviL [449]
3 years ago
9

The degree to which a weak base dissociates is given by the base-ionization constant, Kb. For the generic weak base, B B(aq)+H2O

(l)⇌BH+(aq)+OH−(aq) this constant is given by Kb=[BH+][OH−][B] Strong bases will have a higher Kb value. Similarly, strong bases will have a higher percent ionization value. Percent ionization=[OH−] equilibrium[B] initial×100% Strong bases, for which Kb is very large, ionize completely (100%). For weak bases, the percent ionization changes with concentration. The more dilute the solution, the greater the percent ionization. Ammonia, NH3, is a weak base with a Kb value of 1.8×10−5.partA What is the pH of a 0.245 M ammonia solution?partB What is the percent ionization of ammonia at this concentration?
Chemistry
1 answer:
Colt1911 [192]3 years ago
6 0

Answer:

pH of a 0,245 M ammonia solution is 11,3 and percent ionization is 0,86%

Explanation:

For the equilibrium buffer of NH₃:

NH₃ + H₂O ⇄ NH₄⁺ + OH⁻; kb = 1,8x10⁻⁵

kb = [NH₄⁺] [OH⁻] / [NH₃] <em>(1)</em>

When 0,245 M of NH₃ is added, the equilibrium concentrations are:

[NH₃] = 0,245 - x

[NH₄⁺] = x

[OH⁻] = x.

Replacing this values in (1)

1,8x10^{-5} = \frac{x^2}{0,245 - x}

x² + 1,8x10⁻⁵x - 4,41x10⁻⁶ = 0

Solving for x:

x = -0,00211 No physical sense. There are not negative concentrations.

x = 0,00211 Real answer

Thus [OH⁻] in equilibrium is 0,00211 M.

As pOH = -log [OH⁻] and 14 = pH + pOH

pH of 0,00211 M is <em>11,3</em>

It is possible to calculate the percent ionization thus:

Percent ionization = [OH−] equilibrium / [B] initial×100%

Replacing:

0,00211 / 0,245 × 100 = <em>0,86%</em>

I hope it helps!

You might be interested in
You have 35 ml of water and u drop a rock in so now it is 40ml of water what is the volume of the rock
Soloha48 [4]
Okay
40ml-35ml=5ml
5ml is the volume of the rock
1ml=1cm3
hence the volume of the rock is 5cm3
3 0
3 years ago
A student wants to compare how easily a metal and a plastic spoon of the same temperature can transfer thermal energy. Which of
Artist 52 [7]
Measure the effort required to bend each spoon.

5 0
3 years ago
Read 2 more answers
A roller coaster track is 3,000 meters long. It takes 100 seconds totravel once around the roller coaster. What is the average s
postnew [5]
The rollercoaster went 200 miles.
3 0
2 years ago
Read 2 more answers
What are two factors that affect an objects kinetic energy
Bad White [126]
Potential energy and height; best guess;)
8 0
3 years ago
Read 2 more answers
Select the correct answer.
givi [52]

Answer:

{1s^2 2s^2 2p^6} 3s^2 3p^4

{Ne}3s^2 3p^4

Explanation:

i didnt understand the rest of that but this is the e- configuration on top and the bottom is noble gas configuration

6 0
3 years ago
Other questions:
  • List common properties of bonds
    6·1 answer
  • 2NaHCO3--&gt;Na2CO3+H2O+CO2
    7·1 answer
  • 6. What is the relatonship between wavelength and frequency
    15·1 answer
  • Which describes the letter that belongs where the question mark is?
    10·2 answers
  • if the pressure, volume, and the number of moles of a gas are known, which is needed to calculate the universal gas constant fro
    6·2 answers
  • Write the chemical equation: <br> hydrogen peroxide decomposes to yield oxygen gas and water.
    12·1 answer
  • Phenolphthalein meaning
    8·2 answers
  • When a basketball is left outside in the cold it goes flat because the volume of air inside the
    11·1 answer
  • Carbon dioxide and water are produced when ethanol, C2H5OH, is burned in oxygen. The number of moles of CO2 that is produced whe
    14·1 answer
  • The half-life of tritium (h) is 12 years. How long does it take for 16. 0 ng of tritium to decay to the point where 2. 0 ng rema
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!