How many anions are there in 2.50 g of MgBr2?

2.50 g MgBr2 x 1 mole MgBr2/184 g x 2 mole Br/mole MgBr2 = 0.0272 moles Br^-
0.0272 moles Br^- x 6.02x10^23 anions/mole = 1.6x10^22 anions