Mass Spectra Interpretation: ALKANES

Mass Spectra Interpretation: ALKANES

No. of Questions= 7

ELECTRON IMPACT MASS SPECTROMETRY PRODUCED THE SPECTRA BELOW. MANY PEAKS ARE LABELLED TO AID INTERPRETATION: M/Z (RELATIVE ABUNDANCE). LOOK AT THE HINTS AND FOLLOW THE WEB REFERENCE LINK FOR HELP. YOU WILL NEED A PERIODIC TABLE, A TABLE OF COMMON ISOTOPES (WHICH YOU CAN FIND IN THE WEB REFERENCE), A CALCULATOR, AND SCRATCH PAPER TO WORK THIS QUIZ.

1.	The molecular ion in the spectrum below is 58. What alkyl group was lost to form the intense fragment at m/z 43?
		Web Reference
		Click on image to enlarge
	a)	methyl (CH3)
	b)	ethyl (CH3CH2)
	c)	propyl (CH3CH2CH2)
2.	For this same spectrum, choose the compound that the spectrum represents.
		Web Reference
		Click on image to enlarge
	a)	2-methyl butane
	b)	butane
	c)	pentane
	d)	cyclobutane
	e)	1-butene
3.	The highest cluster of peaks in a spectrum may contain the molecular ion and its isotope peak(s). In the spectrum below, how many carbons are represented by the molecular ion peak 72 and its isotope peak 73?
		Web Reference
		Click on image to enlarge
	a)	3
	b)	4
	c)	5
	d)	6
4.	For this same spectrum, choose the compound that the spectrum represents.
		Web Reference
		Click on image to enlarge
	a)	hexane
	b)	1-pentene
	c)	2-methyl pentane
	d)	2,2-dimethyl propane
	e)	pentane
5.	Choose the compound that this spectrum represents.
		Web Reference
		Click on image to enlarge
	a)	2,2-dimethyl pentane
	b)	2-methyl hexane
	c)	heptane
	d)	3,3-dimethyl butane
	e)	octane
6.	Choose the compound that this spectrum represents.
		Web Reference
		Click on image to enlarge
	a)	octane
	b)	2,2-dimethyl pentane
	c)	2-methyl hexane
	d)	3,3-dimethyl butane
	e)	heptane
7.	Choose the compound that this spectrum represents.
		Web Reference
		Click on image to enlarge
	a)	3-methyl pentane
	b)	2,2-dimethyl butane
	c)	heptane
	d)	hexane
	e)	2-methyl pentane