Stoichiometry question number 3?

Question

Note- please do not just solve these for the answer, but give a brief explanation as to how you got them, so I can refresh my memory on how to do this branch of Chemistry again. Thanks!!!

3) The equation for one of the reactions in the process of reducing iron ore to the metal is:

Fe2O3(s) + 3CO(g) --> 2Fe(s) + 3CO2(g)

a) what is the maximum mass or iron, in grams, that can be obtained from 454g (1.00 lb) of Iron (III) oxide?

b) What mass of CO is required to reduce the Iron (III) oxide to Iron metal?

--------------------------------------...

thank-you!

Answer 1

Here are the steps.  You do the math.

1. Convert grams Fe2O3 to moles.

2. From the equation, moles Fe produced is 2 times moles Fe2O3 used.

3. Convert moles Fe to grams Fe.

4. From the equation it takes 3 moles CO to react with one mole Fe2O3, so moles CO needed equals 3 times moles Fe2O3.

5. Convert moles CO to grams.

Answer 2

a) Just relate the moles of Fe to the moles of Fe2O3

You'll need the molecular weight if Fe2O3 and Fe

This is the general strategy for the problem:

mass of Fe2O3 x molar mass of Fe2O2 x moles of Fe/ mol Fe2O2 x molar mass of Fe

the molar mass of Fe2O3 is 159.7 g/mol

the molar mass of Fe is 55.85 g/ mol

there are 2 moles of Fe per 1 mole of Fe2O3

In dimensional analysis we want certain units to cancel out, so this is how you would set up the problem:

(454 g Fe2O3)(1 mol Fe2O3/ 159.7 g Fe2O3)(2 mol Fe/ 1 mol Fe2O3)(55.85 g Fe/ 1 mol Fe) = 317.54 g Fe will be your maximum (ideal) yield

b) Its the same idea, except this time instead of relating the moles of Fe to the moles of Fe2O3 relate the moles of CO to the moles of Fe2O3 and use the molar mass of CO. Try it.

Answer 3

a) convert mass to number of moles using the molar mass of iron oxide.

Using stoichiometry, find how many moles of iron are made.

Convert moles to mass

b) Use the stoichiometry to find out how many moles are needed

Convert moles to mass using molar mass of CO

good luck!