# Finding the excess after the reaction is complete (chem 101)

1. Sep 12, 2010

### legendarium

When 2.0mL of 1.5M Ammonium Phosphate is mixed with 1.00 mL of 0.75 M Ferrous Acetate.

The problem itself is in multiple parts.
I have already found the limited reactant. But i need help finding "the grams of the reactant in excess after the reaction is complete."

What i have so far...
Ferrous Acetate is limiting reactant with theoretical yield of of 0.09g.
Ammonium Phosphate has 0.54g of a theoretical yield.

3. The attempt at a solution

I have attempted this multiple times and have been searching the web as to how to do it...no positive results so far.

2. Sep 12, 2010

### Staff: Mentor

Write reaction equation.

How many moles of each reactant?

How many moles of product?

How many moles of each reactant was consumed during the reaction?

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3. Sep 12, 2010

### legendarium

balanced equation:
2(NH4)3PO4 +3Fe(C2H202)2 -> 6NH4(C2H202) + Fe2(PO4)2

Im not sure how to obtain the rest of what you are asking.

4. Sep 12, 2010

### Staff: Mentor

I already told you in the other thread. You know volume and concentration - start with concentration definition, solve for number of moles of substance.

5. Sep 12, 2010

### legendarium

We have
3e-3 moles of Ammonium Phosphate and
7.5e-4 moles of Ferrous Acetate

How do i find how many moles of the product i have and how many moles are consumed?

6. Sep 13, 2010

### Staff: Mentor

Time to write and use reaction equation. You need to know what are stoichiometric coefficients.

I think I have already directed you to the page where I explained how to read reaction equation.

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methods

7. Sep 25, 2010

### legendarium

Yes, thank you.