Question

Hi, I am trying to determine the formula of the coordination complex Cr(NH3)Cl. The question states use the percentages obtained for Cl, Cr, and NH3 and determine the formula of the Cr-complex Legna synthesized.

I found the percent of Cr^3+ 19.97% and NH3 39.14%. How can I find the percent of Cl and the formula for the Cr complex?

Answer 1

mass percent of Cl = 100 - (19.97 + 39.14) =40.89 %

moles of Cl = 59.11 / 35.5 = 1.665

moles of Cr+3 = 19.97 / 52 = 0.384

moles of NH3 = 39.14 / 17 = 2.30

Cr      NH3         Cl

0.384             2.30               1.665

1                    6                     4

formula of complex = Cr(NH3)6Cl4