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brittykitty
Oct 26, 2008, 04:28 PM
What is the mass of 5.00moles of potassium dichromate?

I was guessing it would be 294.18 x 5.00 but I could be wrong, any suggestions? Thanks :)
What would the correct formula be?

Capuchin
Oct 26, 2008, 04:32 PM
If 294.18 is the correctly determined molecular mass, then yes you're right. Do you understand why?

Important: what are the units?

brittykitty
Oct 27, 2008, 02:38 PM
Would it be?
1470.9 g/mol?

Because you have the mass times how many moles the potassium dichromate has and that should give you the molecular mass.. ahh its so confusing.

Capuchin
Oct 27, 2008, 02:50 PM
The 294.18 is g/mol. Your result is just g. the mass.

brittykitty
Oct 27, 2008, 02:53 PM
So its 294.18g?

brittykitty
Oct 27, 2008, 02:54 PM
My teacher is marking it out of 2 marks so that why I figured there had to be some kind of formula to figure out

Capuchin
Oct 27, 2008, 03:05 PM
You have to correctly determine the molecular mass first, which is 294.18 and i assume you have the working for, then the mass you need to multiply that by the number of moles.

\frac{g}{mol}*mol = g

brittykitty
Oct 27, 2008, 03:18 PM
294.18 x 5.00 = 1470.9 g?