Recent content by hc772

  1. H

    Dissociation constant from absorbance

    So if the absorbance of 0.335 is only due to the picric anion the concentration of the picric anion of the solution is as follows: 0.335 = (1.973)CA CA= 0.173 M Ka = [A+]/[NaA][NaOH] = [0.173]/[.12][1] = 1.44 M
  2. H

    Dissociation constant from absorbance

    the molar absorptivity of the picric acid would be 0.581 = a(0.300 M) a= (0.581/0.300) = 1.937 M and for the mixture of sodium picrate and NaOH it would be 0.335 = a1(0.120 M) + a2(1 M) This gives me two unknowns for one equation. can I use the molar absorptivity of the picric acid...
  3. H

    Dissociation constant from absorbance

    So to find the equilibrium concentrations I did: NaA + NaOH ---> A + OH + 2Na 0.012 M 1.0 M 0 0 - -x -x +x +x - 0.12 - x 1.0 -x x x - Kc = [A][OH]/[NaH][NaOH] = (0.12 -x)(1.0 -x)/(x)(x)...
  4. H

    Dissociation constant from absorbance

    I thought I was given the concentrations in the question? will the [OH]- not matter because [H]+ >> [OH]-?
  5. H

    Dissociation constant from absorbance

    Homework Statement A 0.120 M solution of sodium picrate ina 1 M sodium hydroxide solution was observed to have an absorbance of 0.335, due only to the absorption by the picrate anion. In the same spectrophotometer cell and at the same wavelength as in the previous measurement, a 0.300 M...
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