Question

F 100.0 g of iron three hydroxide is mixed with 80.0 g of sulfuric acid acid what will be the limiting reactant

Answer 1

The balanced equation for the reaction;

2Fe(OH)₃ + 3H₂SO₄ $\to$ Fe(SO4)₃ + 6H₂O

Moles of Iron(III)hydroxide available

1mole $\implies$ 107g

? $\implies$ 100g

$=\dfrac{1molx100g}{107g}$

= 0.9346mol

Moles of H2SO4 required to completely react with 100g of Iron (III) hydroxide;

Mole ratio of Fe(OH)₃ : H₂SO₄ = 2:3

Moles of H2SO4 $=\dfrac{3}{2} x0.9346 = 1.4019mol$

Moles of H2SO4 available $= \dfrac{mass}{RFM} = \dfrac{80g}{98g/mol} = 0.8163mol$

Therefore, the moles of H₂SO₄ available are less than required, hence H₂SO₄ is the limiting reagent