Analytical Chemistry ( Second ) ❤️

28 Questions | Total Attempts: 50

SettingsSettingsSettings
Please wait...
Analytical Chemistry ( Second )

اللهم رحمة و نور لعمر وتالا ❤️


Questions and Answers
  • 1. 
    All  of these sentences are correct except :
    • A. 

      Keq0    takes  in consideration the ionic strength 

    • B. 

      Keq  = keq0     anly at fi < 1

    • C. 

      When there is an ionic strength , the molar conc. is not equal to the effective  concentration 

  • 2. 
    All of these sentences about activity coefficient are correct except :
    • A. 

      ( f =1 ) , for undissociated acid 

    • B. 

       f is a function of the total electrolyte concentration of the solution 

    • C. 

      The activity coefficient is more accurate in mixed electrolyte solution than in single one 

  • 3. 
    1*10-4 M of a weak electrolyte AB , dissociates to A+  & B-  with keq0  = 2*10-8 . calculate the % dissociation in the presence of 0.1 M diverse salt ( fA = 0.6    , f= 0.7 ) 
    • A. 

      2.6 % 

    • B. 

      1.4 %

    • C. 

      4.1 %

    • D. 

      2.2% 

  • 4. 
    In  case of combination of 2 ionic species , the addition of diverse salt shifts the reaction to the left ( reactant باتجاه ال  ) & decreases Complex's formation constant ( keq).
    • A. 

      True

    • B. 

      False

  • 5. 
    Keq , pka , PH  are independent on ionic strength for the reaction involving chared species 
    • A. 

      True

    • B. 

      False

  • 6. 
    Calculate the precent dissociation for 0.09 M HCN 
    • A. 

      0.27 %

    • B. 

      0.012 %

    • C. 

      0.009 %

    • D. 

      0.027 %

  • 7. 
    Calculate the PH of a solution of 5*10-3 M C6H5COOH , ka = 6.3*10-5 in the presence of 0.05 M k2SO4 ( aH = 9 Angstrom , aC6H5COO  = 6 Angstrom  ) 
    • A. 

      3.25

    • B. 

      2.18

    • C. 

      3.18

    • D. 

      3.6

  • 8. 
    It is based on the low of conservation and # of atom in the reaction is constant 
    • A. 

      Mass balance equation 

    • B. 

      Debye and Huekel equation 

    • C. 

      Charge balance equation 

  • 9. 
    The charge balance equation of 2 moles of Na2SO4 that is added into 1 L water is : 
    • A. 

      [Na+] + [H+] = [OH-] +2* [SO4-2]    

    • B. 

      [OH-] + [Na+] = [SO4-2] + [H+]

    • C. 

      [Na+] + [H+] = [OH-] + [SO4-2]  

  • 10. 
    One of these sentences is incorrect during adding a diverse salt to an aqueous solution : 
    • A. 

      An increase in the dissociation of a weak electrolyte 

    • B. 

      The diverse ion shields the ions of weak acid 

    • C. 

      Increase the  effective conc. 

    • D. 

      Effect keq value 

  • 11. 
    Calculate the ionic strength of 0.2 M solution of KNO3 and 0.2 M of Al2SO3 
    • A. 

      0.2

    • B. 

      3

    • C. 

      3.2

    • D. 

      0.6

  • 12. 
    Very weak acid dont contribute to the ionic strenght 
    • A. 

      True

    • B. 

      False

  • 13. 
    Which of the following is stating that :  " the rate of a chemical reaction is proportional to the active masses of the reacting substances present any time " : 
    • A. 

      Le Chatelier principle  

    • B. 

      Mass balance equation 

    • C. 

      The low of mass action 

  • 14. 
    The reaction " A + B <-------> 2C + D + Heat "  will procced from right to left when : 
    • A. 

      Sufficient conc. of C  is present 

    • B. 

      Increase the temprature 

    • C. 

      Increase [D]

    • D. 

      Increase the pressure 

    • E. 

      All of the above 

  • 15. 
    One of the following does not affect neither keq nor the position of chemical reactions :
    • A. 

      Temperature

    • B. 

      Pressure

    • C. 

      Catalyst

  • 16. 
    The wrong sentence is :
    • A. 

      The larger keq  of an acid , the stronger will be acid 

    • B. 

      Keq  value depends on the solvent of the rxn 

    • C. 

      The equilibrium constant give an idea about the rate of reaction  how to fast 

  • 17. 
    The conjugate base H2PO-is
    • A. 

      H3PO4

    • B. 

      HPO4-2

    • C. 

      PO4-3

    • D. 

      None of the above 

  • 18. 
    The pH, POH, [OH-​​​​​​] respectively 2*10-5 HNO3
    • A. 

      9.3, 4.69, 5*10-10

    • B. 

      8.6, 5.4, 2.5*10-9

    • C. 

      None of the above 

  • 19. 
    The correct statement of the following is 
    • A. 

      The POH for 1*10-8  M HBr is 6

    • B. 

      Acidity increase as pka increase 

    • C. 

      PH=log1/[H+]

  • 20. 
    Solution of. 01M HA has PH=2.8, the estimated Ka of the acid is
    • A. 

      1.6*10-3

    • B. 

      2.5*10-5

    • C. 

      3*10-4

  • 21. 
    Which of the following statements is not correct 
    • A. 

      A bronsted acid is an electron pair donor

    • B. 

      A lewis base is an electron pair donor

    • C. 

      The conjugate acid of NHis NH4+

  • 22. 
    The self-ionization of a solvent to give cation and anion 
    • A. 

      Autoprotolysis

    • B. 

      Dissociation 

    • C. 

      Shielding 

  • 23. 
    The normal blood PH is 7.35-7.45 this value must be measured at
    • A. 

      25 c

    • B. 

      37 c

    • C. 

      36-38 c

  • 24. 
    The PH of a solution prepared by mixing 2 ml of monoprotic strong acid of PH=3 and 3 ml of monohydroxy strong base of PH=10 is
    • A. 

      10

    • B. 

      13

    • C. 

      3.4

    • D. 

      10.6

  • 25. 
    The POH of 1*10-7 M solution of HCl is
    • A. 

      6.79

    • B. 

      7.21

    • C. 

      7

Back to Top Back to top