[Rutherford]

I know that in acidic solution Cr₂O₇^2- and CrO₄^2- get reduced to Cr³⁺, but under what conditions Cr³⁺ gets oxidized to CrO₄^2-, and what conditions are required to make Cr₂O₇^2-?

[Borek]

what conditions are required to make Cr₂O₇^2-?

Just a matter of pH:

2CrO₄^2- + 2H⁺ Cr₂O₇^2- + H₂O

[Rutherford]

Then, acidic solution=dichromate, basic solution=chromate?

[Borek]

Or mixture of both.

[Rutherford]

Okay, thanks.