chemistry*

posted by .

Over the years, the thermite reaction has been used for welding railroad rails, in incendiary bombs, and to ignite solid-fuel rocket motors. The reaction is given below.

Fe2O3(s) + 2 Al(s) -->2 Fe(l) + Al2O3(s)

What masses of iron(III) oxide and aluminum must be used to produce 30.0 g iron? What is the maximum mass of aluminum oxide that could be produced?

OK, I'm stuck on the limiting reagent part...

My work:
30g Fe x (1 mol/55.85g Fe) =0.5372

ALUMINUM:
0.5372 mol Fe x (2 mol Al/ 2 mol Fe) = 0.5372 mol Al

0.5372 mol Al x (26.98 g Al/1 mol)=14.194 g Al

IRON(III) OXIDE
0.5372 mol Fe x (1 mol Fe2O3/2 mol Fe)=.2686mol Fe2O3

.2686 mol Fe2O3 x (55.85*2+16*3) g / 1 mol
=42.895 g Fe2O3

What is the maximum mass of aluminum oxide that could be produced? ---limiting reagent problem?

I take all the masses and convert them to moles and divide by their coefficients
30.0 g Fe = .5372 mol Fe / 2=.2686
14.194 g Al = .5261 mol Al / 2 = .2630
42.895 g Fe2O3 = .2686 / 1 = .2686

Their numbers are pretty similar, probably the only difference is the aluminum, so is that the limiting one?

.5261 mol Al x (1 mol Al2O3/2 mol Al) = .2630 mol Al2O3??

.2630 g Al2O3 x (1 mol/101.96 g)= .002579 g

please help me on this last part.

  • chemistry* -

    This is not a limiting reagent problem.
    The only error I see right off is mass Al needed is closer to 14.5 than to 14.2. I think you just punched the wrong button. As for the maximum amount of Al2O3, just take the moles Fe, convert to moles Al2O3, then to grams and you have it.

  • chemistry* -

    thanks!

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    Over the years, the thermite reaction has been used for welding railroad rails, in incendiary bombs, and to ignite solid-fuel rocket motors. The reaction is given below. Fe2O3(s) + 2 Al(s) 2 Fe(l) + Al2O3(s) What masses of iron(III) …
  2. Chemistry*

    Oh sorry I forgot the arrows! Over the years, the thermite reaction has been used for welding railroad rails, in incendiary bombs, and to ignite solid-fuel rocket motors. The reaction is given below. Fe2O3(s) + 2 Al(s) -->2 Fe(l) …
  3. chemistry

    the thermite reaction was previously used to weld the rails of railroad tracks together. the reaction is: Fe2O3(s)+ 2Al(s)--> 2Fe(l)+ Al2O3(s) (2Fe and 3 oxygen) (2Al and 3 oxygen) what masses of iron(III) oxie and aluminum must …
  4. chem

    over the years, the thermite reaction has been used for welding railorad rails, in incendiary bombs, and to ignite solid fuel rocket motors. The reaction: Fe2O3(s) + 2 Al (s) -> 2 Fe(l) + Al2O3 (s) What masses of iron ( III) oxide …
  5. chemistry

    Thermite mixtures are used for certain types of weldings and the thermite reaction is highly exothermic. Given delta H= -852 KJ/mol, 1 mole of granular Fe2O3 and 2 moles of granular aluminum are mixed at room temperature and the reaction …
  6. chemistry

    Thermite mixtures are used for certain types of weldings and the thermite reaction is highly exothermic. Given delta H= -852 KJ/mol, 1 mole of granular Fe2O3 and 2 moles of granular aluminum are mixed at room temperature and the reaction …
  7. Chemistry

    Over the years, the thermite reaction (mixing of solid iron (III) oxide with aluminum metal) has been used for welding railroad rails, in incendiary bombs, and to ignite solid-fuel rocket motors. A. Write a balanced equation representing …
  8. Chemistry

    Over the years, the thermite reaction has been used for welding railroad rails, in incendiary bombs, and to ignite solid-fuel rocket motors. The reaction is the following. Cr2O3(s) + 2 Al(s) → 2 Cr(l) + Al2O3(s) What masses of …
  9. Chemistry

    Over the years, the thermjte reaction has been used for welding railroads, in incendiary bombs, and to ignite solid fuel rocket monitors. The reaction is Fe2O3(s) + Al(s) ---> 2Fe(l) + AI2O3(s). What mass of iron (iii) oxide(rust) …
  10. Chemistry

    Over the years, the thermjte reaction has been used for welding railroads, in incendiary bombs, and to ignite solid fuel rocket monitors. The reaction is Fe2O3(s) + Al(s) ---> 2Fe(l) + AI2O3(s). What mass of iron (iii) oxide(rust) …

More Similar Questions