Mass of substance =250mg=0.250g Mass of AgBr=141mg=0.141g 1 mole of AgBr=1g atom of Br 188g of AgBr=80g of Br ∴ fof AgBr contain bromine =80g 0.141g of AgBr contain bromine =
80
188
×0.141=0.06g 0.06g of bromine is present in 0.250g of organic compound ∴% of bromine =