The number of moles of [Co(NH3)5SO4]Br=0.02×1=0.02mol
The number of moles of [Co(NH3)5Br]SO4=0.02×1=0.02mol
The total volume of the solution becomes two Litres after mixing.
Following precipitation reactions occur:
[Co(NH3)5SO4]Br0.01mol+AgNO3excess→AgBr↓0.01mol
[Co(NH3)5Br]SO40.01mol+BaCl2excess→BaSO4↓0.01mol