Assumed that the precipitates are BaSO4 and BaF2, that way I got their mass together to be 3.95g, while in the problem it is given as 3.96g. The difference is very small, so it is probably correct.
Yes, this is what I think is happening too.
(SOFN)
3 + 9H
2O + (4.5)Ba(OAc)
2 3BaSO
4 + (1.5)BaF
2 + 3NH
4OAc + 6AcOH
Your 3.95 is probably the result of a rounding error. Here is my calculation:
1.00 g (SOFN)
3 => 1000/243.2 = 4.112 mmol
Therefore we expect: 4.112*1.5 = 6.168 mmol BaF
2 => 6.168*175.3 = 1081 mg
And also: 4.112*3 = 12.336 mmol BaSO
4 => 12.336*233.4 = 2879 mg
Total = 1081 + 2879 = 3960 mg
=> 3.96 g