Chemistry

The dissociation for a weak base BOH in water found to be 1.25 x 10^-6. What is the concentration of H+ in a 3.2M soluton of BOH.

  1. 👍 0
  2. 👎 0
  3. 👁 193
asked by LT
  1. Do you mean the dissociation for a weak base is 1.25 x 10^-5 or the dissociation constant is 1.25 x 10^-5?

    1. 👍 0
    2. 👎 0
  2. constant
    sorry :(

    1. 👍 0
    2. 👎 0
    posted by LT
  3. BOH <==> B^+ + OH^-

    Kb = (B^+)(OH^-)/(BOH) = 1.25 x 10^-6

    Have you been introduced to the ICE chart?
    Initial = I
    change = C
    equilibrium = E

    Initial concns (before any dissociation):
    (BOH) = 3.2 M
    (B^+) = 0
    (OH^-) = 0

    change in concns (after dissociation):
    (B^+) = y
    (OH^-) = y
    (BOH) = -y

    equilibrium concns:
    (B^+) = 0 + y = y
    (OH^-) = 0 + y = y
    (BOH) = 3.2 - y = 3.2-y

    Plug the equilibrium values into the Kb expression and solve for y. You will get a quadratic which you can solve with the quadratic formula OR you can make the simplifying assumption and see if that will work. At any rate, y = (OH^-) so you take the - log to get pOH, then subtract from 14 to get pH, then convert to (H^+).

    1. 👍 0
    2. 👎 0
  4. I got the pH how do i turn that into (H+)

    1. 👍 0
    2. 👎 0
    posted by LT
  5. pH = -log(H^+)
    Say pH = 4.3.
    Then 4.3 = -log(H^+)
    -4.3 = log(H^+)
    Now enter -4.3 into your calculator, then hit the 10x button and up will pop 5.01187 x 10^-5. Of course you would round that to 5.01 x 10^-5 M

    1. 👍 0
    2. 👎 0

Respond to this Question

First Name

Your Response

Similar Questions

  1. Chemistry

    In the titration of a weak acid with a strong base, the pH at the equivalence point is affected mostly by a.hydrolysis (reaction with water) of the weak acid b.the dissociation of water molecules c.the presence of excess base

    asked by Cheryl on May 26, 2011
  2. Chemistry 12

    name a compound that acts as a weak base? methanol? define the term weak bronsted-lowry base im not sure how to put this in words, but a weak base is found when you got a strong acid, when your ka is high, kb will be low.

    asked by Shreya on January 25, 2013
  3. AP Chemistry

    Write the expression of for the base dissociation constant for hydrazine, N2H4, a weak base. Hydrazine reacts with water to form the N2H5+ ion.

    asked by Angie on January 11, 2010
  4. chemistry

    1. An aqueous solution of weak base B of unknown concentration is tritrated with a known concentration of strong acid, HA. (a) Write the balanced chemical equation for this acid-base reaction, identifying the conjugate acid/base

    asked by Phuong on April 8, 2011
  5. Chemistry

    Provide equations for each of the following: a. Dissociation of a strong base in water solution b. Ionization of a strong acid in water solution: c. Ionization of a weak acid in water solution: d. Ionization of a weak base in

    asked by ASAP!! on April 29, 2014
  6. chemistry

    if 0.4M NaOH is titrated with 0.4M HF, how do we calcualte the ph at equivalence. The book assumes each is 1L, but why do we use 1L * chemistry - Dr.Jim, Thursday, November 11, 2010 at 5:31am HF is a weak acid, so you need the

    asked by flame on November 11, 2010
  7. Chemistry

    If an equal number of moles of the weak acid HOCN and the strong base KOH are added to water, the resulting solution will be acidic, basic or neutral? There is a complicated answer and a sensible answer. Both arrive at the same

    asked by Joel on April 27, 2007
  8. Chemistry

    Can someone check my answer and let me know me if the are right or wrong. 1. What is the maximum amount of KCl that can dissolve in 600 g of water? (The solubility of KCl is 34 g/100 g H₂O at 20°C.) * 34 g 204 g ***** 2040 g 3.

    asked by Lydia on March 13, 2017
  9. Chemistry 2 - Acids and Bases

    Hydrazine (NH2NH2) is a weak base that ionizes in water as follows. NH2NH2(aq) + H2O(l) HNH2NH2^+(aq) + OH^−(aq) Calculate the concentration of OH^− ions in a 0.20 M solution of hydrazine, given that the base-dissociation

    asked by Jamie on February 28, 2018
  10. chemical and ionic equlibrium

    1. calculate H+ ion concentrates in 0.10 m acetic acid solutions. Given that dissociation constant of acetic acid in water is 1.8 * 10^-5 ? 2. Calculate the concentration of H+ and OH- in a 0.05 m HNO3 solutions at 25^0c ? 3. The

    asked by pramod on March 31, 2010

More Similar Questions