What is the percentage #"ammonium"# content in #"ammonium dichromate"#?

1 Answer
Jan 27, 2017

In #(NH_4)_2Cr_2O_7#............?

Explanation:

The molecular mass of #"ammonium dichromate"# is #252.07*g*mol^-1#. We nominate the #NH_4^+# unit as the cation. This has a mass of #18.04*g*mol^-1#.

And thus percentage of cation by mass is:

#(2xx18.04*g*mol^-1)/(252.07*g*mol^-1)xx100%~=14%.#

What is the percentage by mass of metal?