If 0.50 mole of is mixed with 0.20 mole of , the maximum number of moles of that can be formed is
- A.0.70
- B.0.50
- C.0.20
- D.0.10
Show answer and solution
Correct option: D
Solution
The balanced reaction is: 3 BaCl₂ + 2 Na₃PO₄ → Ba₃(PO₄)₂ + 6 NaCl.
Check both reactants as potential limiting reagents:
- From 0.50 mol BaCl₂: moles of Ba₃(PO₄)₂ = 0.50 × (1/3) = 0.167 mol
- From 0.20 mol Na₃PO₄: moles of Ba₃(PO₄)₂ = 0.20 × (1/2) = 0.10 mol
Na₃PO₄ gives the smaller amount, so it is the limiting reagent, and the maximum moles of Ba₃(PO₄)₂ formed is 0.10.
Check both reactants as potential limiting reagents:
- From 0.50 mol BaCl₂: moles of Ba₃(PO₄)₂ = 0.50 × (1/3) = 0.167 mol
- From 0.20 mol Na₃PO₄: moles of Ba₃(PO₄)₂ = 0.20 × (1/2) = 0.10 mol
Na₃PO₄ gives the smaller amount, so it is the limiting reagent, and the maximum moles of Ba₃(PO₄)₂ formed is 0.10.
[1981]