Answer:
The % yield is 64.38 %
Explanation:
Step 1: Data given
Mass of Ca3(PO4)2 = 26.8 grams
Mass of H2SO4 = 54.3 grams
Mass of H3PO4 formed = 10.9 grams
Molar mass of Ca3(PO4)2 =310.18 g/mol
Molar mass of H2SO4 = 98.08 g/mol
Molar mass of H3PO4 = 97.99 g/mol
Step 2: The balanced equation
Ca3(PO4)2 + 3 H2SO4 → 2 H3PO4 + 3 CaSO4
Step 3: Calculate moles Ca3(PO4)2
Moles Ca3(PO4)2 = mass Ca3(PO4)2 / molar mass Ca3(PO4)2
Moles Ca3(PO4)2 = 26.8 grams / 310.18 g/mol
Moles Ca3(PO4)2 = 0.0864 moles
Step 4: Calculate moles H2SO4
Moles H2SO4 = 54.3 grams / 98.08 g/mol
Moles H2SO4 = 0.554 moles
Step 5: Calculate limiting reactant
For 1 mol Ca3(PO4)2 we need 3 moles H2SO4 to produce 2 moles H3PO4 and 3 CaSO4
Ca3(PO4)2 is the limiting reactant. It will completely be consumed. (0.0864 moles).
H2SO4 is in excess. There will react 3*0.0864 = 0.2592 moles
There will remain: 0.554 - 0.2592 = 0.2948 moles
Step 6: Calculate moles H3PO4
For 1 mol Ca3(PO4)2 we need 3 moles H2SO4 to produce 2 moles H3PO4 and 3 CaSO4
For 0.0864 moles we'll have 2*0.0864 = 0.1728 moles H3PO4
Step 7: Calculate mass H3PO4
Mass H3PO4 = moles H3PO4 * molar mass H3PO4
Mass H3PO4 = 0.1728 moles * 97.99 g/mol
Mass H3PO4 = 16.93 grams
Step 8: Calculate percent yield
% yield = (actual yield / theoretical yield)*100%
% yield = (10.9/16.93)*100 %
% yield = 64.38 %
The % yield is 64.38 %