# How to solve this compound question?

1. Dec 16, 2008

### transgalactic

i got this formula

$2Fe +3O_2 -> 2FeO_3$

how many grams of Fe and litters of oxigen do i need
in order to get 0.5 kilogram of

$Fe_2O_3$

i can find how much grams weighs each mole of each molecule?

i dont know how to do the rest

??

2. Dec 16, 2008

### Staff: Mentor

3. Dec 17, 2008

### transgalactic

ok i understand
3 moles of
$O_2$
can react at most with 2 moles of Fe

how do i transform the volume of a gas into grams?

4. Dec 17, 2008

### Staff: Mentor

pV=nRT, ideal gas equation.

5. Dec 17, 2008

### transgalactic

ok by pst 22.4 litters for every mole of gas
i can find the weight of each mole
what now?

6. Dec 17, 2008

### Staff: Mentor

Now you start thinking on your own, we are not here to spoonfeed you.

How many moles of product?

How many moles of reactants needed?