When iodide ions (I-) are added to a solution of iron(III) ions (Fe3+), an equilibrium mixture is formed. a) State a colour change you would expect to see when aqueous iodide ions, I- (aq), are mixed with aqueous iron(III) ions, Fe3+(aq)?

b) What ions are present in the equilibrium mixture?

c) Describe a simple chemical test you could carry out to show the presence of iodide ions, I- (aq), in the equilibrium mixture?

the answer would be 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