2) (25 points) The mass spectrum of a given molecule is shown below 100 80 60 40
ID: 573076 • Letter: 2
Question
2) (25 points) The mass spectrum of a given molecule is shown below 100 80 60 40 10 20 30 40 50 60 70 80 90 100 110 120 m/z a) Using the information provided in this mass spectrum (and only the information in the mass spectrum), indicate which of the molecular formula shown below are possible for this molecule (put OK in the box). For those that are NOT possible, provide a short explanation why they can be ruled out, An example has been done for vou C9H2 C/H ratio too high Too many unsats CsHsF C6HioN2 C3H7FO3 C3H4C12 C7H120 C2H7FN202 CsH12F2 C6H602 C6H6S C6H5FN C4H8F2O C3H7CIO2 CsH14 CSH4N20 C6H3Cl CsH203Explanation / Answer
C3H4Cl2 (NOT OK) Molecular weight is high
Ans b: The molecular formula is C8H14. The IR spectra shows a alkyne C-H stretching at 3300 cm-1. The iR spectra shows a Alkyl C-H stretch between 2800-2900 cm-1. There is a overtone of alkyne C-H at 1250 cm-1. There is a alkyne C-H bend at 620 cm-1. The triple bond is at the terminal position of the compound that is confirmed by IR.
Ans c: The structure of the compound is Oct-1-yne. The molecular weight of the compound is 110 gm/mole as seen in mass spectra as a molecular ion peak at 110 m/z. The structure is also consistent with the data in IR spectrum which is already answered.
NOTE: There is no facility of drawing the structure so I havent drawn.
MOLECULAR FORMULA MOLECULAR WEIGHT (gm/mol) MOLECULAR FORMULA MOLECULAR WEIGHT (gm/mol) MOLECULAR FORMULA MOLECULAR WEIGHT (gm/mol) C9H2 (NOT OK) C/H ratio high Too many unsaturation 111 C6H10N2 (NOT OK) Molecular weight is more 120 C3H7FO3 (NOT OK) Valency is not satisfied in drawing any kind of structure.No possibility of any organic structure 110 C5H3FN2 (NOT OK) Valency is not satisfied in drawing any kind of structure.No possibility of any organic structure 110C3H4Cl2 (NOT OK) Molecular weight is high
111 C7H12O (NOT OK) Molecular weight is high 112 C2H7FN2O2 (NOT OK) Valency is not satisfied in drawing any kind of structure. No possibility of any organic structure 110 C5H12F2 (NOT OK) Molecular weight is more 112 C6H6O2 (OK) But possibility of aromatic structure 110 C6H6S (OK) But possibility of aromatic structure 110 C6H5FN (NOT OK) Valency is not satisfied in drawing any kind of structure. No possibility of any organic structure 110 C4H8F2O (NOT OK) Valency is not satisfied in drawing any kind of structure. No possibility of any organic structure 110 C3H7ClO2 (NOT OK) Valency is not satisfied in drawing any kind of structure. No possibility of any organic structure 110.5 C8H14 (OK) 110 C5H4N2O (NOT OK) Molecular weight is less 108 C6H3Cl (NOT OK) Valency is not satisfied in drawing any kind of structure. No possibility of any organic structure 110.5 C4H2N2O2 (NOT OK) Valency is not satisfied in drawing any kind of structure. No possibility of any organic structure 110 C5H2O3 (NOT OK) Valency is not satisfied in drawing any kind of structure. No possibility of any organic structure. 110Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.