The polymer polylactic acid, PLA, shown above, is used to make soluble stitches which are absorbed by the body following surgery - VCE - SSCE Chemistry - Question 4 - 2009 - Paper 1
Question 4
The polymer polylactic acid, PLA, shown above, is used to make soluble stitches which are absorbed by the body following surgery.
Other than the peak given by the T... show full transcript
Worked Solution & Example Answer:The polymer polylactic acid, PLA, shown above, is used to make soluble stitches which are absorbed by the body following surgery - VCE - SSCE Chemistry - Question 4 - 2009 - Paper 1
Step 1
A. one set of peaks in the 'H NMR
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Answer
This option would imply a uniform environment for all hydrogen atoms in the molecule, which is not the case for PLA as it has different groups that produce distinct NMR signals.
Step 2
B. two sets of peaks in the 'H NMR
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Answer
This could suggest that there are two distinct types of hydrogens in the structure. However, the complexity of the PLA structure suggests more variations than just two.
Step 3
C. three sets of peaks in the 'H NMR
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Answer
While this indicates some variation among hydrogen types, it still does not account for the full complexity of the NMR analysis of PLA.
Step 4
D. four sets of peaks in the 'H NMR
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Answer
This is the correct choice as PLA consists of multiple types of hydrogen environments, leading to at least four distinct sets of peaks in the 'H NMR spectrum.
