//example-17.1
//page no-511
//given
//density of nickel and nickel oxide (NiO)
rhom=8900  //kg/m^3
rhoc=7080  //kg/m^3
//molecular weight of nickel and nickel oxide
Mm=58.51
Mc=74.71
//molar volumes are
Vm=Mm/rhom  //m^3/mol
Vc=Mc/rhoc  //m^3/mol
printf ("it is clear that Vc>Vm, so a protective film will form over nickel")