An impure sample of zinc (Zn) is treated with an excess of sulfuric acid (H2SO4) to form zinc sulfate (ZnSO4) and molecular hydrogen (H2).

(a) Write a balanced equation for the reaction.

Zn(s) + →

(b) How many moles are in 3.70 g of pure zinc?

_ mol

(c) How many moles of hydrogen gas are formed if one mole of zinc is treated with excess sulfuric acid?

_mol

(d) If 3.70 g of pure Zn is treated with excess sulfuric acid, how many grams of hydrogen could be collected?

_ g

(e) If 0.0660 g of H2 is obtained from 3.70 g of impure sample, what is the percent purity of the sample?

_ %

the answer is d. 74.02

the answer is barium and copper bromide

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