1. A Cr³⁺ solution is prepared.  Some is added to crystallizing dishes A and B.
2. NaOH is added to the Cr³⁺ solution. Some is poured into dish C.
3. More NaOH is added to the solution. Some of this is poured into dish D.
4. 3% H₂O₂ is added to the rest of the solution. Some of this is pour into dish E.  HCl is added to this dish.

• Solution E is compared with A, C, and D, and HCl is added to them.
• HCl and granulated Zn are added to dish B.
• BaCl₂ is added to the remaining solution. HCl is then added.  Finally, Pb(NO₃)₂ is added.

Violet solution of Cr(H₂O)₆ ³⁺.

The color of the solution changes from violet to an "acid green".

Green Cr(OH)₃ precipitates from the green solution.  More base will cause the solid to redissolve to give a green chromite Cr(OH)₄ ^-solution. 

The green solution changes to orange as the CrO₄^2-/Cr₂O₇^2- ions are formed.

After the HCl is added a series of erratic color changes are observed.  When the reaction is complete the solution is green.

Solution A remains violet. Solution C changes from green back to violet. Solution D produces another green solution.

When the solution becomes acidic, several pieces of Zn are added to the dish.  The bright blue color of Cr²⁺ (aq) will be visible momentarily, but air oxidation rapidly converts this to a green solution.

A yellow precipitate of BaCrO₄ will form.  Adding HCl will redissolve the precipitate and produce an orange-yellow solution.  Pb(NO₃)₂ produces another yellow precipitate, PbCrO₄.