Use the information provided by these spectra to answer the following questions - VCE - SSCE Chemistry - Question 5 - 2009 - Paper 1
Question 5
Use the information provided by these spectra to answer the following questions.
a. What is the molecular formula of this molecule?
b. How many different proton ... show full transcript
Worked Solution & Example Answer:Use the information provided by these spectra to answer the following questions - VCE - SSCE Chemistry - Question 5 - 2009 - Paper 1
Step 1
What is the molecular formula of this molecule?
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Answer
The molecular formula for the molecule is C₂H₆O₂. This indicates that there are two carbon atoms, six hydrogen atoms, and two oxygen atoms in the compound.
Step 2
How many different proton environments are there in this molecule?
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Answer
There are two different proton environments in this molecule. One environment is associated with the hydrogen atoms attached to the carbon atoms, while the other is linked to the hydrogen atoms of the hydroxyl groups.
Step 3
Draw the structure of the unknown molecule, clearly showing all bonds.
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The structure of the unknown molecule can be represented as follows:
H H
\
C - O - H
/ \
H C
| |
H O - H
This diagram illustrates the connectivity of the atoms and shows all the bonds.
Step 4
Explain how the structure of the compound you have drawn in part c. is consistent with its IR spectrum.
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The IR spectrum of the compound shows a broad peak in the region of 2500-3300 cm⁻¹, which indicates the presence of O-H stretching vibrations typical of alcohols. This confirms the existence of hydroxyl groups in the molecule as depicted in the structure drawn.
Step 5
Name the compound you have drawn in part c.
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Answer
The compound drawn in part c is commonly known as ethylene glycol.
