Finding the repeating unit of polymerisation given two constituent moleculesNumber of hydrogen molecules...

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Finding the repeating unit of polymerisation given two constituent molecules


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4












$begingroup$



The compounds $ce{H2NCH2CH2NH2}$ and $ce{HOOCCH2COOH}$ react to form a polymer. What is the structure of the repeating unit of the polymer?



A. $require{enclose}ce{enclose{horizontalstrike}{(}HNCH2CONHCH2CH2NHCOenclose{horizontalstrike}{)}}$
B. $ce{enclose{horizontalstrike}{(}HNCH2CH2NHCOCH2COenclose{horizontalstrike}{)}}$
C. $ce{enclose{horizontalstrike}{(}OCCH2CONHCH2NHCOenclose{horizontalstrike}{)}}$
D. $ce{enclose{horizontalstrike}{(}HNCH2CH2NHCOCH2NHenclose{horizontalstrike}{)}}$




I came across this question which requires me to find the structure of the repeating unit of the polymer made by the reaction of two different compounds. However, I am not sure as to which repeating unit would suffice for this particular polymer.



As far as I know, there should be double bonds present at the ends of the repeating unit, so that the pi bond can break and allow the formation of additional bonds, and hence, a chain of molecules. However, using that line of thought I cannot seem to figure out the answer to the question.



I just need a direction, a hint or a clue as to how I should approach problems like such.










share|improve this question











$endgroup$








  • 4




    $begingroup$
    What you are mentioning is addition polymerization which malonic acid and ethylenediamine wouldn't dream of doing. Condensation occurs, rather.
    $endgroup$
    – William R. Ebenezer
    15 hours ago










  • $begingroup$
    Draw out the skeletal structures with different colors so you can see how the building blocks combine. If you have monomers A and B, and A can't link with A and B can't link with B, the only polymer you can get is A-B-A-B-A...
    $endgroup$
    – Karsten Theis
    13 hours ago






  • 1




    $begingroup$
    "As far as I know, there should be double bonds present at the ends of the repeating unit"; This is not correct.
    $endgroup$
    – A.K.
    8 hours ago
















4












$begingroup$



The compounds $ce{H2NCH2CH2NH2}$ and $ce{HOOCCH2COOH}$ react to form a polymer. What is the structure of the repeating unit of the polymer?



A. $require{enclose}ce{enclose{horizontalstrike}{(}HNCH2CONHCH2CH2NHCOenclose{horizontalstrike}{)}}$
B. $ce{enclose{horizontalstrike}{(}HNCH2CH2NHCOCH2COenclose{horizontalstrike}{)}}$
C. $ce{enclose{horizontalstrike}{(}OCCH2CONHCH2NHCOenclose{horizontalstrike}{)}}$
D. $ce{enclose{horizontalstrike}{(}HNCH2CH2NHCOCH2NHenclose{horizontalstrike}{)}}$




I came across this question which requires me to find the structure of the repeating unit of the polymer made by the reaction of two different compounds. However, I am not sure as to which repeating unit would suffice for this particular polymer.



As far as I know, there should be double bonds present at the ends of the repeating unit, so that the pi bond can break and allow the formation of additional bonds, and hence, a chain of molecules. However, using that line of thought I cannot seem to figure out the answer to the question.



I just need a direction, a hint or a clue as to how I should approach problems like such.










share|improve this question











$endgroup$








  • 4




    $begingroup$
    What you are mentioning is addition polymerization which malonic acid and ethylenediamine wouldn't dream of doing. Condensation occurs, rather.
    $endgroup$
    – William R. Ebenezer
    15 hours ago










  • $begingroup$
    Draw out the skeletal structures with different colors so you can see how the building blocks combine. If you have monomers A and B, and A can't link with A and B can't link with B, the only polymer you can get is A-B-A-B-A...
    $endgroup$
    – Karsten Theis
    13 hours ago






  • 1




    $begingroup$
    "As far as I know, there should be double bonds present at the ends of the repeating unit"; This is not correct.
    $endgroup$
    – A.K.
    8 hours ago














4












4








4





$begingroup$



The compounds $ce{H2NCH2CH2NH2}$ and $ce{HOOCCH2COOH}$ react to form a polymer. What is the structure of the repeating unit of the polymer?



A. $require{enclose}ce{enclose{horizontalstrike}{(}HNCH2CONHCH2CH2NHCOenclose{horizontalstrike}{)}}$
B. $ce{enclose{horizontalstrike}{(}HNCH2CH2NHCOCH2COenclose{horizontalstrike}{)}}$
C. $ce{enclose{horizontalstrike}{(}OCCH2CONHCH2NHCOenclose{horizontalstrike}{)}}$
D. $ce{enclose{horizontalstrike}{(}HNCH2CH2NHCOCH2NHenclose{horizontalstrike}{)}}$




I came across this question which requires me to find the structure of the repeating unit of the polymer made by the reaction of two different compounds. However, I am not sure as to which repeating unit would suffice for this particular polymer.



As far as I know, there should be double bonds present at the ends of the repeating unit, so that the pi bond can break and allow the formation of additional bonds, and hence, a chain of molecules. However, using that line of thought I cannot seem to figure out the answer to the question.



I just need a direction, a hint or a clue as to how I should approach problems like such.










share|improve this question











$endgroup$





The compounds $ce{H2NCH2CH2NH2}$ and $ce{HOOCCH2COOH}$ react to form a polymer. What is the structure of the repeating unit of the polymer?



A. $require{enclose}ce{enclose{horizontalstrike}{(}HNCH2CONHCH2CH2NHCOenclose{horizontalstrike}{)}}$
B. $ce{enclose{horizontalstrike}{(}HNCH2CH2NHCOCH2COenclose{horizontalstrike}{)}}$
C. $ce{enclose{horizontalstrike}{(}OCCH2CONHCH2NHCOenclose{horizontalstrike}{)}}$
D. $ce{enclose{horizontalstrike}{(}HNCH2CH2NHCOCH2NHenclose{horizontalstrike}{)}}$




I came across this question which requires me to find the structure of the repeating unit of the polymer made by the reaction of two different compounds. However, I am not sure as to which repeating unit would suffice for this particular polymer.



As far as I know, there should be double bonds present at the ends of the repeating unit, so that the pi bond can break and allow the formation of additional bonds, and hence, a chain of molecules. However, using that line of thought I cannot seem to figure out the answer to the question.



I just need a direction, a hint or a clue as to how I should approach problems like such.







polymers






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited 13 hours ago









Karsten Theis

4,082542




4,082542










asked 15 hours ago









Selena CarlosSelena Carlos

567




567








  • 4




    $begingroup$
    What you are mentioning is addition polymerization which malonic acid and ethylenediamine wouldn't dream of doing. Condensation occurs, rather.
    $endgroup$
    – William R. Ebenezer
    15 hours ago










  • $begingroup$
    Draw out the skeletal structures with different colors so you can see how the building blocks combine. If you have monomers A and B, and A can't link with A and B can't link with B, the only polymer you can get is A-B-A-B-A...
    $endgroup$
    – Karsten Theis
    13 hours ago






  • 1




    $begingroup$
    "As far as I know, there should be double bonds present at the ends of the repeating unit"; This is not correct.
    $endgroup$
    – A.K.
    8 hours ago














  • 4




    $begingroup$
    What you are mentioning is addition polymerization which malonic acid and ethylenediamine wouldn't dream of doing. Condensation occurs, rather.
    $endgroup$
    – William R. Ebenezer
    15 hours ago










  • $begingroup$
    Draw out the skeletal structures with different colors so you can see how the building blocks combine. If you have monomers A and B, and A can't link with A and B can't link with B, the only polymer you can get is A-B-A-B-A...
    $endgroup$
    – Karsten Theis
    13 hours ago






  • 1




    $begingroup$
    "As far as I know, there should be double bonds present at the ends of the repeating unit"; This is not correct.
    $endgroup$
    – A.K.
    8 hours ago








4




4




$begingroup$
What you are mentioning is addition polymerization which malonic acid and ethylenediamine wouldn't dream of doing. Condensation occurs, rather.
$endgroup$
– William R. Ebenezer
15 hours ago




$begingroup$
What you are mentioning is addition polymerization which malonic acid and ethylenediamine wouldn't dream of doing. Condensation occurs, rather.
$endgroup$
– William R. Ebenezer
15 hours ago












$begingroup$
Draw out the skeletal structures with different colors so you can see how the building blocks combine. If you have monomers A and B, and A can't link with A and B can't link with B, the only polymer you can get is A-B-A-B-A...
$endgroup$
– Karsten Theis
13 hours ago




$begingroup$
Draw out the skeletal structures with different colors so you can see how the building blocks combine. If you have monomers A and B, and A can't link with A and B can't link with B, the only polymer you can get is A-B-A-B-A...
$endgroup$
– Karsten Theis
13 hours ago




1




1




$begingroup$
"As far as I know, there should be double bonds present at the ends of the repeating unit"; This is not correct.
$endgroup$
– A.K.
8 hours ago




$begingroup$
"As far as I know, there should be double bonds present at the ends of the repeating unit"; This is not correct.
$endgroup$
– A.K.
8 hours ago










2 Answers
2






active

oldest

votes


















6












$begingroup$

You are starting out with amino groups on one monomer and carboxylate groups on the other monomer. As William R. Ebenezer states in the comment, these combine via condensation (to form an amide, which is written as -NHCO- or -CONH- in condensed formulas). enter image description here



The linkages in the answer choices between repeating units are not visible until you write another repeating unit next to the ones shown. A. and B. show amide linkages between repeating units, while C. and D. show something else.



Here is the exercise rewritten to emphasize the amide bonds in the repeating units:




The compounds $ce{H2NCH2CH2NH2}$ and $ce{HOOCCH2COOH}$ react to form a polymer. What is the structure of the repeating unit of the polymer?



A. $require{enclose}ce{enclose{horizontalstrike}{(}HNCH2CO-NHCH2CH2NH-COenclose{horizontalstrike}{)}}$
B. $ce{enclose{horizontalstrike}{(}HNCH2CH2NH-COCH2COenclose{horizontalstrike}{)}}$
C. $ce{enclose{horizontalstrike}{(}OCCH2CO-NHCH2NH-COenclose{horizontalstrike}{)}}$
D. $ce{enclose{horizontalstrike}{(}HNCH2CH2NH-COCH2NHenclose{horizontalstrike}{)}}$




Now that we emphasized the amide linkages, you can see that the first monomer in A, the second monomer in C and the second monomer in D don't match your starting materials. We can also exclude C. and D. because repeating units are not linked via amides. The answer has to be B.






share|improve this answer











$endgroup$





















    0












    $begingroup$

    You got the answer you have looking for in Karsten Theis' answer. However, your statement of "as far as I know, there should be double bonds present at the ends of the repeating unit" is not entirely correct for all polymers in general (see A.K.'s comment). Yes, some have double bonds within the chain and at the end. But, most polymers forms without assistance from double bonds and, hence do not contain double bonds (unsaturations). Here is two best known polymers we used in our day to day life:



    FabricPolymer



    Both ate fabrics and none has end unsaturation. The reaction shows you that none need unsaturation to condense.






    share|improve this answer









    $endgroup$














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      2 Answers
      2






      active

      oldest

      votes








      2 Answers
      2






      active

      oldest

      votes









      active

      oldest

      votes






      active

      oldest

      votes









      6












      $begingroup$

      You are starting out with amino groups on one monomer and carboxylate groups on the other monomer. As William R. Ebenezer states in the comment, these combine via condensation (to form an amide, which is written as -NHCO- or -CONH- in condensed formulas). enter image description here



      The linkages in the answer choices between repeating units are not visible until you write another repeating unit next to the ones shown. A. and B. show amide linkages between repeating units, while C. and D. show something else.



      Here is the exercise rewritten to emphasize the amide bonds in the repeating units:




      The compounds $ce{H2NCH2CH2NH2}$ and $ce{HOOCCH2COOH}$ react to form a polymer. What is the structure of the repeating unit of the polymer?



      A. $require{enclose}ce{enclose{horizontalstrike}{(}HNCH2CO-NHCH2CH2NH-COenclose{horizontalstrike}{)}}$
      B. $ce{enclose{horizontalstrike}{(}HNCH2CH2NH-COCH2COenclose{horizontalstrike}{)}}$
      C. $ce{enclose{horizontalstrike}{(}OCCH2CO-NHCH2NH-COenclose{horizontalstrike}{)}}$
      D. $ce{enclose{horizontalstrike}{(}HNCH2CH2NH-COCH2NHenclose{horizontalstrike}{)}}$




      Now that we emphasized the amide linkages, you can see that the first monomer in A, the second monomer in C and the second monomer in D don't match your starting materials. We can also exclude C. and D. because repeating units are not linked via amides. The answer has to be B.






      share|improve this answer











      $endgroup$


















        6












        $begingroup$

        You are starting out with amino groups on one monomer and carboxylate groups on the other monomer. As William R. Ebenezer states in the comment, these combine via condensation (to form an amide, which is written as -NHCO- or -CONH- in condensed formulas). enter image description here



        The linkages in the answer choices between repeating units are not visible until you write another repeating unit next to the ones shown. A. and B. show amide linkages between repeating units, while C. and D. show something else.



        Here is the exercise rewritten to emphasize the amide bonds in the repeating units:




        The compounds $ce{H2NCH2CH2NH2}$ and $ce{HOOCCH2COOH}$ react to form a polymer. What is the structure of the repeating unit of the polymer?



        A. $require{enclose}ce{enclose{horizontalstrike}{(}HNCH2CO-NHCH2CH2NH-COenclose{horizontalstrike}{)}}$
        B. $ce{enclose{horizontalstrike}{(}HNCH2CH2NH-COCH2COenclose{horizontalstrike}{)}}$
        C. $ce{enclose{horizontalstrike}{(}OCCH2CO-NHCH2NH-COenclose{horizontalstrike}{)}}$
        D. $ce{enclose{horizontalstrike}{(}HNCH2CH2NH-COCH2NHenclose{horizontalstrike}{)}}$




        Now that we emphasized the amide linkages, you can see that the first monomer in A, the second monomer in C and the second monomer in D don't match your starting materials. We can also exclude C. and D. because repeating units are not linked via amides. The answer has to be B.






        share|improve this answer











        $endgroup$
















          6












          6








          6





          $begingroup$

          You are starting out with amino groups on one monomer and carboxylate groups on the other monomer. As William R. Ebenezer states in the comment, these combine via condensation (to form an amide, which is written as -NHCO- or -CONH- in condensed formulas). enter image description here



          The linkages in the answer choices between repeating units are not visible until you write another repeating unit next to the ones shown. A. and B. show amide linkages between repeating units, while C. and D. show something else.



          Here is the exercise rewritten to emphasize the amide bonds in the repeating units:




          The compounds $ce{H2NCH2CH2NH2}$ and $ce{HOOCCH2COOH}$ react to form a polymer. What is the structure of the repeating unit of the polymer?



          A. $require{enclose}ce{enclose{horizontalstrike}{(}HNCH2CO-NHCH2CH2NH-COenclose{horizontalstrike}{)}}$
          B. $ce{enclose{horizontalstrike}{(}HNCH2CH2NH-COCH2COenclose{horizontalstrike}{)}}$
          C. $ce{enclose{horizontalstrike}{(}OCCH2CO-NHCH2NH-COenclose{horizontalstrike}{)}}$
          D. $ce{enclose{horizontalstrike}{(}HNCH2CH2NH-COCH2NHenclose{horizontalstrike}{)}}$




          Now that we emphasized the amide linkages, you can see that the first monomer in A, the second monomer in C and the second monomer in D don't match your starting materials. We can also exclude C. and D. because repeating units are not linked via amides. The answer has to be B.






          share|improve this answer











          $endgroup$



          You are starting out with amino groups on one monomer and carboxylate groups on the other monomer. As William R. Ebenezer states in the comment, these combine via condensation (to form an amide, which is written as -NHCO- or -CONH- in condensed formulas). enter image description here



          The linkages in the answer choices between repeating units are not visible until you write another repeating unit next to the ones shown. A. and B. show amide linkages between repeating units, while C. and D. show something else.



          Here is the exercise rewritten to emphasize the amide bonds in the repeating units:




          The compounds $ce{H2NCH2CH2NH2}$ and $ce{HOOCCH2COOH}$ react to form a polymer. What is the structure of the repeating unit of the polymer?



          A. $require{enclose}ce{enclose{horizontalstrike}{(}HNCH2CO-NHCH2CH2NH-COenclose{horizontalstrike}{)}}$
          B. $ce{enclose{horizontalstrike}{(}HNCH2CH2NH-COCH2COenclose{horizontalstrike}{)}}$
          C. $ce{enclose{horizontalstrike}{(}OCCH2CO-NHCH2NH-COenclose{horizontalstrike}{)}}$
          D. $ce{enclose{horizontalstrike}{(}HNCH2CH2NH-COCH2NHenclose{horizontalstrike}{)}}$




          Now that we emphasized the amide linkages, you can see that the first monomer in A, the second monomer in C and the second monomer in D don't match your starting materials. We can also exclude C. and D. because repeating units are not linked via amides. The answer has to be B.







          share|improve this answer














          share|improve this answer



          share|improve this answer








          edited 12 hours ago

























          answered 13 hours ago









          Karsten TheisKarsten Theis

          4,082542




          4,082542























              0












              $begingroup$

              You got the answer you have looking for in Karsten Theis' answer. However, your statement of "as far as I know, there should be double bonds present at the ends of the repeating unit" is not entirely correct for all polymers in general (see A.K.'s comment). Yes, some have double bonds within the chain and at the end. But, most polymers forms without assistance from double bonds and, hence do not contain double bonds (unsaturations). Here is two best known polymers we used in our day to day life:



              FabricPolymer



              Both ate fabrics and none has end unsaturation. The reaction shows you that none need unsaturation to condense.






              share|improve this answer









              $endgroup$


















                0












                $begingroup$

                You got the answer you have looking for in Karsten Theis' answer. However, your statement of "as far as I know, there should be double bonds present at the ends of the repeating unit" is not entirely correct for all polymers in general (see A.K.'s comment). Yes, some have double bonds within the chain and at the end. But, most polymers forms without assistance from double bonds and, hence do not contain double bonds (unsaturations). Here is two best known polymers we used in our day to day life:



                FabricPolymer



                Both ate fabrics and none has end unsaturation. The reaction shows you that none need unsaturation to condense.






                share|improve this answer









                $endgroup$
















                  0












                  0








                  0





                  $begingroup$

                  You got the answer you have looking for in Karsten Theis' answer. However, your statement of "as far as I know, there should be double bonds present at the ends of the repeating unit" is not entirely correct for all polymers in general (see A.K.'s comment). Yes, some have double bonds within the chain and at the end. But, most polymers forms without assistance from double bonds and, hence do not contain double bonds (unsaturations). Here is two best known polymers we used in our day to day life:



                  FabricPolymer



                  Both ate fabrics and none has end unsaturation. The reaction shows you that none need unsaturation to condense.






                  share|improve this answer









                  $endgroup$



                  You got the answer you have looking for in Karsten Theis' answer. However, your statement of "as far as I know, there should be double bonds present at the ends of the repeating unit" is not entirely correct for all polymers in general (see A.K.'s comment). Yes, some have double bonds within the chain and at the end. But, most polymers forms without assistance from double bonds and, hence do not contain double bonds (unsaturations). Here is two best known polymers we used in our day to day life:



                  FabricPolymer



                  Both ate fabrics and none has end unsaturation. The reaction shows you that none need unsaturation to condense.







                  share|improve this answer












                  share|improve this answer



                  share|improve this answer










                  answered 1 hour ago









                  Mathew MahindaratneMathew Mahindaratne

                  5,952724




                  5,952724






























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