294 g of potassium dichromate contains 52 g of chromium and 39 g of potassium. What is the mass percent of oxygen in the compound?

1 Answer
May 21, 2016

Answer:

Well, clearly it is #"Mass of oxygen"/"Mass of potassium dichromate"# #xx# #100%#.

Explanation:

You have already down the hard yards: the mass of oxygen is the mass of the sample LESS the mass of the metals.

#"%Oxygen by mass"# #=# #((294-52-39)*g)/(294*g)xx100%# #=# #??%#

I make that about #66%#, but don't trust my arithmetic!