When chromium metal is added to nitric acid, the following reaction takes place Cr (s) + 6 HNO₃ (aq) → Cr(NO₃)₃ (aq) + 3 H₂O (l) + 3 NO₂ (g)
Calculate the volume of NO₂ gas (in L) collected over water at 40.0 °C when 11.1 g of chromium is added to excess nitric acid if the total pressure is 675 torr. The vapor pressure of water at 40.0 °C is 55.3 torr.

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