In gas chromatography, compounds may be separated based on their molecular weight - HSC - SSCE Chemistry - Question 11 - 2004 - Paper 1
Question 11
In gas chromatography, compounds may be separated based on their molecular weight. The smaller the molecular weight the more quickly the compound is detected. A gas ... show full transcript
Worked Solution & Example Answer:In gas chromatography, compounds may be separated based on their molecular weight - HSC - SSCE Chemistry - Question 11 - 2004 - Paper 1
Step 1
Identify the substances and their molecular weights
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
In the mixture, we have:
1-hexanol (C6H14) - molecular weight: 102 g/mol
1-octanol (C8H18) - molecular weight: 130 g/mol
1-heptanol (C7H16) - molecular weight: 116 g/mol
1-pentanol (C5H12) - molecular weight: 88 g/mol
The order of elution in gas chromatography is typically based on molecular weight, with lower molecular weight compounds eluting first.
Step 2
Determine the position of peak X
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
From the graph, peak X appears first among the detected compounds. This indicates that it corresponds to the compound with the lowest molecular weight.
Step 3
Conclusion about peak X
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Given that 1-pentanol has the lowest molecular weight (88 g/mol), peak X corresponds to 1-pentanol, which is option (D).
