The theoretical yield of BaCO3 is 5.5
The theoretical yield is the yield calculated from the stoichiometry of the reaction. The equation of the reaction is;
Ba(NO3)2(aq) + Na2CO3 (aq) ------> BaCO3(s) + 2NaNO3(aq)
Number of moles of limiting reactant: 0.4 M × 70/1000 = 0.028 moles
Since the reaction is 1:1,om;y 1 mole of BaCO3 is formed. Hence, mass of BaCO3 = 0.028 moles × 197 g/mol = 5.5g
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