Respuesta :
Answer:
0.513 iron per gram of steel is the concentration of iron in the steel sample.
Explanation:
[tex]MnO_4^{-} +8 H^+ +5Fe^{2 +}\rightarrow Mn^}{2 +} + 5 Fe^{3 +} + 4 H_2O[/tex]
Molarity of [tex]KMnO_4[/tex] solution = 0.100 M
Volume of [tex]KMnO_4[/tex] solution = 43.16 mL = 0.04316 L( 1mL=0.001 L)
Moles of [tex]KMnO_4[/tex] = n
[tex]Molarity=\frac{Moles}{Volume (L)}[/tex]
[tex]n=0.100 M\times 0.04316 L=0.004316 mol[/tex]
1 mole of [tex]KMnO_4[/tex] gives 1 mole of potassium ion and manganate ions.
Moles of [tex]MnO_4^{-}=0.004316 mol[/tex]
According to reaction, 1 mole of manganate ion reacts with 5 moles of ferrous ions.Then 0.004316 mole of manganate ion will react with L:
[tex]\frac{5}{1}\times 0.004316mol=0.02158 mol[/tex] of ferrous ions
Mass of 0.02158 moles of ferrous ion:
0.02158 mol × 55.845 g/mol = 1.2051 g
Mass of steel sample = 2.349 g
Concentration on iron in sample :
[tex]\frac{1.2051 g\text{iron}}{2.349 g\text{steel}}=0.513[/tex] iron per gram of steel
