First write the formula and make sure it is balance
MgSO4 + BaCl2 --> MgCl2 + BaSO4
then, we need to determine which reactant is the limiting reagent. using their respective molar masses.
1.20 g MgSO4 x (1 mole MgSO4/ 120.3 g)=0.00998 moles
10.0 g BaCl2 x (1 mole BaCl/ 172 g) = 0.0580 moles
Since MgSO4 give the less amount of moles, MgSO4 is the limiting reagent.
0.00998 moles MgSO4 (1 mole BaSO4/1 mole MgSO4) (233.3 g/ 1 mole BaSO4) = 2.34 grams