The percentage yield would be 90.42%
First, the balanced equation of the reaction is as follows:
Ca₃(PO₄)₂ (s) + 3H₂SO₄ (aq) → 2H₃PO₄ (aq) + 3CaSO₄ (aq)
From the equation, the mole ratio of Ca₃(PO₄)₂ and H₃PO₄ is 1:2
Recall that: mole= mass/molar mass
Mole of Ca₃(PO₄)₂ = 23.7/310.174
                = 0.076 mole
Mole ratio of Ca₃(PO₄)₂ and H₃PO₄ = 1:2
Mole of H₃PO₄ = 0.076 x 2
             = 0.153 mole
Theoretical yield (in g) of H₃PO₄ = mole x molar mass
                  = 0.153 x 97.994
                  = 14.82 g
Percentage yield of H₃PO₄ = actual yield/theoretical yield x 100
                     = 13.4/14.82 x 100
                     = 90.42%
More on percentage yield of reactions can be found here: brainly.com/question/20758645
