Chemistry

posted by .

Which ligand binds the tightest?

Ligand A, with a Kd of 10^-9M

Ligand B, with a Kd of 10^-3M

Ligand C, with a percent occupancy of 30% at one micromolar

Ligand D, with a percent occupancy of 80% at 10 nm

  • Chemistry -

    the relative molecular mass of lead 2 trioxonitrate V is (pb=180,N=14, O=16).

  • Chemistry/Biochemistry -

    Since the dissociation constant is equal to the inverse of the association constant, it is possible to figure this out. It would be the one with the lowest dissociation contant or the one with the highest association constant. Ligand A has a lower dissociation constant then B, so B is eliminated. Since 30% occupancy requires the ligand must greater than 3 times the number of it's dissociation constant, and the units for the dissociation constant are given in M. After converting everything to M, the equations for ligand C and D will be the following:


    1x10^-6=3(Kd)

    10x10^-9=8(Kd)

    Solving for Kd,


    Ligand C's Kd=3.3 x10^-7

    Ligand D's Kd=1.2 x10^-9

    The answer is Ligand A

  • Chemistry -

    The answer is A, however the explanation previously given is incorrect.

    The correct explanation is that the association fraction (theta) is given by the expression:

    theta = [L]/([L] +Kd)

    where [L] = ligand native concentration and Kd = the dissociation constant.

    Given this equation, you can then solve for Kd in (C) and (D):

    0.3 = 1 x 10^-6/(1 x 10^-6 + Kd)
    Kd = 2.3 x 10^-6

    0.8 = 1 x 10^-9/(1 x 10^-9 + Kd)
    Kd = 2.5 x 10^-9

    This allows you to compare each Kd, and conclude that (A) has the lowest dissociation constant, and, therefore, the greatest association constant of the ligand (the ligand binds the tightest).

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Electrochemistry

    Does the addition of ligands such as aqueous ammonia affect the potential difference of an electrochemical cell?
  2. chemistry

    given: Ferrocene, Acetylferrocene, 1, 1' Diacetylferrocene What part of the ferrocene compound(s) is(are) responsible for creating a dipole moment What type of molecular orbitals does the cyclopentadienyl ligand use to bond with the …
  3. Ap Chemistry

    How can NH3 be a ligand but NH4+ is not a ligand?
  4. chemistry HELP PLEASE

    write the formulas of the complex ion formed between a) the ligand, Cl-, and the platinum(II) ion with a coordination number of four. b) the ligand, NH3, and the nickel(II( ion with a coordination number of six. c)the ligand, ethylenediamine, …
  5. chemistry

    write the formulas of the complex ion formed between a) the ligand, Cl-, and the platinum(II) ion with a coordination number of four. b) the ligand, NH3, and the nickel(II( ion with a coordination number of six. c)the ligand, ethylenediamine, …
  6. Chemistry

    A metal element (M) forms a hexadentate complex with the ligand ethylenediammine (en). Its formula is M(en)32+. The metal ion and the ligand do not absorb in the visible region of spectrophotometer and a 1.00 cm cuvette, the following …
  7. analytical chemistry

    Consider a general reaction where a ligand L and a metal ion Mn+ form a complex with m number of ligands (L) coordinated to each metal ions. Assume the metal is colorless. The ligand and metal solutions were mixed at molar fractions …
  8. Chemistry

    Explain how a ligand can be both sigma donating and pi donating and give an example of a ligand that does both. Is this ligand a Lewis acid or a Lewis base?
  9. Chemistry

    Explain how a ligand can be both sigma donating and pi donating and give an example of a ligand that does both. Is this ligand a Lewis acid or a Lewis base?
  10. chemistry

    Industrial waste contains Zn(II) and cyanide. The waste is toxic to aquatic species like fish. 1- If the waste consists of water, Zn(II) and cyanide, what ligands might complex with Zn(II)?

More Similar Questions