# Can you make a Lewis structure of dichromate ion, i.e. Cr_2O_7^(2-)?

Apr 27, 2017

$\text{In dichromate..........?}$
For (""^(-)O-)(O=)_2Cr-O-Cr(=O)_2(-O^(-))
Well each chromium centre is tetrahedral to a first approx., so there are $2 \times 6$, and one $\angle C r - O - C r$, so this gives 13 in total. Make a model, and see if you agree with me. (I did not make a model because I am lazy!). I have treated all $\angle O - C r - O$ and $\angle C r - O - C r$ as tetrahedral to a first approx.