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eventob
Feb2-11, 04:30 AM
1. The problem statement, all variables and given/known data
10 g Fe and x ml H2SO4 forms y gFeSO4*7H2O

Write a balanced chemical equation for the reaction, and determine the coeffisients y and x. The H2SO4 is 1 M.


2. Relevant equations
n=V*c
n=m/Fm


3. The attempt at a solution
First thing I was trying to set up the chemical eq:
Fe+H2SO4 => FeSO4*7H2O

But, I'm not sure how to balance the hydrogens and oxygens in the crystal water.

I've also calculated the how many moles 10 g of Fe is.


Any thoughts?

Thanks in advance.

Borek
Feb2-11, 04:42 AM
You need to add water molecules on the left - after all, reaction takes place in a solution. If not, there is no way hydrated salt can be produced.

eventob
Feb2-11, 04:52 AM
Thanks.

But then, do I have to add hydrogen to the right?

Fe+H2SO4 + 7H2O => FeSO4*7H2O + H^+

Borek
Feb2-11, 05:04 AM
Other than water of crystallization it is not different from the reaction between a metal and an acid. I am more than sure that you have covered this reaction earlier, so check your notes and the book. Googling for reaction between metal and acid will also give you the answer.

eventob
Feb2-11, 07:11 AM
Thanks again. :)

I tried to Google it first, but could only find formulas without the crystallization water. So I was not sure how to handle that part. I am currently taking two different chemistry courses, one introductory and one who builds one the knowledge from the introductory course. I've never seen the *H2O part until this reaction. :)

symbolipoint
Feb2-11, 02:23 PM
Writing a balanced reaction should be no big problem. Look at the mole ratios among the parts and the materials. Post #3 reaction is almost, but not yet balanced. No matter, you can still write enough reaction without including the H+ ions.

Use given information and formula weights to account for both grams and moles.
10 grams Fe ----- How many moles?
1 to 1 mole ratio of Fe to FeSO4*7H2O ----- then how many moles and how many grams if starting from 10 grams of Fe ?