3.) One method used in the eighteen century to generate hydrogen was to pass steam through red-hot steel tubes. The following reaction takes place:

3Fe(s)+4H20(g)--->Fe3O4(s)+4H2(g)

2. What mass of iraon will react with 500.0 L of steam at 25 degrees C and 1.00 atm pressure?

3. If 285g of Fe3O4 are formed, what volume of hydrogen, measured at 20 degrees C and 1.06 atm, is produced?

I don't understand have to use which formula to plug in which numbers for number two in order to find the answers, or for number three.

2 answers

3. has questions 2 and 3 included, so its really not one question, its one question with three parts, but i have one part answered i just don't understand these two.
You need to be more specific. I worked problem 3.) for you yesterday and included all the steps, including answers to each step. #2 is worked essentially the say way as is #3. We try very hard to help but help is all we do. You posted three questions and I worked one. I shall be happy to help you work 2 and 3 but I won't do them for you. You may be confused about which numbers to plug into which formulas. Go back over the problem I worked for you. I shall be happy to help you understand the problem I worked. If you understand the steps in that problem then it should be easier to work 2 and 3.