The limiting reactant : Fe
Further explanation
Reaction
3Fe + 4H₂O ⇒ Fe₃O₄ + 4H₂
mass of H₂O = 10 g
mol H₂O (MW=18 g/mol) :
[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{10}{18}=0.56[/tex]
mass of Fe = 16.8 g
mol Fe(MW=56 g/mol) :
[tex]\tt mol=\dfrac{16.8}{56}=0.3[/tex]
Limiting reactant : the smallest ratio between mol : reaction coefficient
Fe :
[tex]\tt \dfrac{0.3}{3}=0.1[/tex]
H₂O :
[tex]\tt \dfrac{0.56}{4}=0.14[/tex]
Fe as limiting reactant
