Although 2,2-dimethylhexane has a molecular weight of 114, no peak is observed at m/z = 114. The base peak in the mass spectrum occurs at M−57. (a) Draw the fragmentation responsible for formation of the M−57 ion. (b) Explain why this cation is the most abundant ion to pass through the spectrometer. (c) Explain why no molecular ions survive long enough to be detected. (d) Can you offer an explanation as to why the M−15 peak is not the base peak?

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer

elements make up everything, and they combine to make compounds.

the answer is c

answer : (a) volume of the gas = 8.67 ×   l

                (b) second virial coefficient b = -1.21226 l/mole

solution :   given,     t = 300k

                                p = 20atm

                                z = 0.86

                                n = 8.2 mmoles = 8.2 × moles

                                r =   0.082 l atm/k/mol

        find,     (a) volume of gas   and (b) second virial coefficient b at 300k.

formula used :            

                          and            

(a)            

                    = \times 0.082\times 300}{20}[/tex]

                    = 8.67 ×   l

(b)      

                    = (0.00867-1) × 8.659

                    = - 8.5839 l/mole