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Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: MissDee on November 05, 2009, 08:52:27 PM

Title: Dumb question about finding molarity when neither solute nor solution..?
Post by: MissDee on November 05, 2009, 08:52:27 PM

2Fe(NH₄)₂(SO₄)₂ x 6H₂O + 3H₂C₂O₄ + H₂O₂ + 3K₂C₂O₄  :rarrow: 2K₃Fe(C₂O₄)₃ X 3H₂O + 4(NH₄)HSO₄ + 8H₂O

I need to calculate the following:

- the number of moles in 33.0 ml of 1.00M H₂C₂O₄
- the number of moles in 20.0 ml of 3% H₂O₂ (which is 1.00M)
- the number of moles in 10.0 ml of saturated K₂C₂O₄ (which is 2.00M)

I originally thought you had to use the formula Molarity = moles solute/liters solution, but nothing is specified, just the information I posted. Do you use it anyway without regards to which is the solute and which is the solution, and just go off the molarity and mL units?

Title: Re: Dumb question about finding molarity when neither solute nor solution..?
Post by: csrscience.com on November 05, 2009, 10:00:28 PM

- the number of moles in 33.0 ml of 1.00M H2C2O4

1.00M is 1mol/1000mLs.
If you have 33ml's you are going to have the same ratio... in order to find this you'd solve for x:

1mol/1000mls = x/33mls
If this doesn't make sense.. I'll try to explain it better...

While this isn't identical, a lot of the concepts are interchangeable when it comes to converting such things.. so you may want to check this out: http://indiescience.org/basetalk/index.php?topic=24.0