Respuesta :
Explanation:
[tex]4 Fe(s) + 3O_2(g)\rightarrow 2Fe_2O_3(s) ,\Delta H = -1652 kJ[/tex]
a) Heat released when 4.48 moles of iron is reacted with excessive oxygen:
According to reaction, when 4 moles of an iron reacts with 3 moles of oxygen it gives 1625 kilo Joules of heat.
Then 4.48 moles of iron will give:
[tex]\frac{1652 kJ}{4}\times 4.48=1850.24 kJ[/tex]
1850.24 kJ of heat is released when 4.48 moles of an iron is reacted with excess oxygen.
b) Heat released when 1.76 mol [tex]Fe_2O_3[/tex] is produced.
According to reaction, when 2 moles of an [tex]Fe_2O_3[/tex] are produced 1625 kilo Joules of heat is released
Then heat released on production of 1.76 mol [tex]Fe_2O_3[/tex] :
[tex]\frac{1652 kJ}{2}\times 1.76=1453.76 kJ[/tex]
1453.76 kJ heat is released when 1.76 mol [tex]Fe_2O_3[/tex] is produced.
c) Heat released when 2.66 grams of iron is reacted with excessive oxygen:
Moles of iron = [tex]\frac{2.66 g}{56 g/mol}=0.0475 mol[/tex]
According to reaction, when 4 moles of an iron reacts with 3 moles of oxygen it gives 1625 kilo Joules of heat.
Then 0.0475 moles of iron will give:
[tex]\frac{1652 kJ}{4}\times 0.0475=19.62 kJ[/tex]
19.62 kJ of heat is released when 2.66 grams of iron is reacted with excessive oxygen.
d) Heat released when 12.8 g Fe and 1.49 g oxygen gas are reacted:
Moles of iron = [tex]\frac{12.8 g}{56 g/mol}=0.2286 mol[/tex]
According to reaction, 4 moles of iron reacts with 3 moles of oxygen.Then 0.2286 mol will react with:
[tex]\frac{3}{4}\times 0.2286 mol=0.17145 mol[/tex] of oxygen
Moles of oxygen = [tex]\frac{1.49 g}{56 g/mol}=0.04656 mol[/tex]
According to reaction, 3 moles of oxygen gas reacts with 4 moles of iron .Then 0.04656 mol will react with:
[tex]\frac{4}{3}\times 0.04656 mol=0.06208 mol[/tex] of iron.
From this we can conclude that oxygen is in limiting amount. So, the amount of energy release will depend upon moles of oxygen gas.
According to reaction, when 4 moles of an iron reacts with 3 moles of oxygen it gives 1625 kilo Joules of heat.
Then 0.04656 moles of oxygen gas will give:
[tex]\frac{1652 kJ}{3}\times 0.04656 =25.7011 kJ[/tex]
25.7011 kJ of Heat is released when 12.8 g Fe and 1.49 g oxygen gas are reacted
