An experimental alloy contained by copper and tantalum of the alloy was dissolved and analyzed gravimetrically.

 

a) the copper was precipitated and weighed as CuO, a mass of 0.1739g was obtained. Calculate the %w/w Cu in the alloy.

 

b) the tantalum was precipitated and weighed as Ta2O5, a mass 0.4748g was obtained. calculate the %w/w Ta in the alloy.

How far have you got so far, and do you know what a mole is?

It's like the no of atom in a subtance, right?

seriously, I'm really don't know how to do it?

I really need it for my test revision

Then you also need to know what a mole is. Google is your friend.

A mole is not just no. of atoms or molecules in a substance.A mole can be defines as a chemical mass unit, defined to be 6.022 x 1023 molecules, atoms, or some other unit. The mass of a mole is the gram formula mass of a substance.

gram formula or atomic mass of CuO is 79.545 g/mol and that is of Ta2O5 is 441.893 g/mol, Cu=53.55g/mol and Ta=180.95g/mol

No. Of. Moles of a substance = Mass of that substance in grams/gram formula mass of that substance

I think you can do it further..... Good luck for your Xams....

Edited March 30, 201015 yr by Chembio
Consecutive posts merged.