According to the activity series, all of the following single replacement reactions occur EXCEPT-
A 3 Mg (s) + 2 AI(NO3)2 (aq) → 3 Mg(NO3)2 (aq) + 2 Al (s)
B 2 Fe (s) + 3 Pb(NO3)2 (aq) → 2 Fe(NO3)2 (aq) + 3 Pb (s)
C Zn (s) + Cu(NO3)2 (aq) → Zn(NO3)2 (aq) + Cu (s)
D 3 Ag (s) + CO(NO3)3 (ag) → 3 AgNO3 (aq) + Co (s)

i believe the answer is a.

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