Question

This question is based on the mass spectrum of diethyl sulfide (CH3CH2SCH2CH3) which can be found at this link... http://webbook.nist.gov/cgi/cbook.cgi?ID=C352932&Mask=200 You will need java to see this spectrum! Identify the ion fragment that has a mass of 29.

a) C2H5SC2H5+

b)C4H10+

c) C2H5+

d) S+

Answer 1

In the given options the Molar mass of C₂H₅⁺ is =(2xAt.mass of C ) + (5xAt.mass of H )

                                                                      = ( 2x12) + (5x1)

                                                                      = 29 g/mol

This is the only fragment having mass 29 so the correct answer is (c)