JohnDoeDDS

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Hello everyone. you ight have read my other post. I am trying to get some help for some chem problems that I have that are due tomorrow morning lol. Yep I saved it last minute because I thought it would be easy but I cant seem to get how to balance equations. In class we did it, and it was so easy and obvious but this one im stuck and I have a test coming up soon and I have no idea how to approach these kind of things. Can some pelase help me out I would appreciate it. Here is the equation:

H2SO4 + Fe(OH)3 --> Fe2(SO4)3 + H2O

Thank you all very much for your help. If you could also explain the answer and how you approached this one I would be extremely grateful. Thanks...

By the way does any1 know of a chem or HW forum or something where I can post these type of questions if I have trouble in the future, so people could help each other out? Or is it just okay to post it here?
 

hb2998

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Its been a long time since G-Chem.. but i'll give it a shot.

3H2SO4 + 2Fe(OH)3 --> Fe2(SO4)3 + 6H2O

There...
Each side should have
2 Fe
3 S
18 O
12 H

Whats the best way... I remember in class way back there was a routine.. Check with your professor.. but in the meanwhile, do what I do. Start with the non O, non H atoms. (Fe, S, etc). You can't have 1/2 H2O... If you do you have to multiply everything so you have a whole number next to each compound. Try to solve many of these problems, once you get it down.. you really won't ever forget how to do them. (I feel your pain.. G-Chem sucks. :smuggrin: )
 
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J

JohnDoeDDS

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hey thanks for helping out. The problem is though that there are so many atoms here so it really threw me off and I did not know where to start. Especiall with two subscripts its really confusing me. Thanks though:)
 

luder98

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To balance this type of equations, you should not look at atoms as individuals. Instead, try to identify group. In this case, instead of balancing S or O, blance the whole group SO4 -2. It will be much less confusing.

Another way of balancing rxn equations in general is to give each coefficient an unknown. Then equate all the elements. In this case, you would do:

aH2SO4 + bFe(OH)3 --> cFe2(SO4)3 + dH2O

H: 2a + 3b = 2d
S: a = 3c
Fe: b = 2c
O: 4a + 3b = 12c + d

You have 4 unknowns and four equations, just solve those equations. This way is long, but will ALWAYS work for ALL reactions. When you encounter some tricky redox rxns, you'll find it very useful.
 

burton117

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JohnDoeDDS said:
By the way does any1 know of a chem or HW forum or something where I can post these type of questions if I have trouble in the future, so people could help each other out? Or is it just okay to post it here?
Physics Forums

The main focus of this forum above is Physics, but they have a small section dedicated to Chemistry as well as Biology topics.
 

Victoria1999

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This problem is extremely easy. You should do it without even thinking.
Good luck :)