20,6 г                                     Х г    2 NaBr       +      Cl2      =       2NaCl       +     Br2n = 2 моль                                n = 2 мольMr = 103 г/моль                      Mr = 58,5 г/мольm=206 г                                    m = 117 г20,6 г NaBr    -    Х г NaCl206 г NaBr    -    117 г NaClm(NaCl) = 20,6 * 117 / 206 = 11,7 г