Final answer:
The color of EBT in a solution containing zinc is wine-red, indicating the formation of a complex between EBT and Zn2+ ions.
Step-by-step explanation:
In solutions that contain zinc such as when having zinc react with hydrochloric acid or copper (II) sulfate, the resultant ion Zn2+ is colorless. However, when the complexometric indicator EBT (Eriochrome Black T) is added to a solution of Zn2+ ions, it forms a wine-red complex.
The specific color change depends on the concentration of zinc ions in the solution as well as the presence of other ions that may also form complexes with EBT. When titrating, the endpoint is indicated by a color change from wine-red to blue when all zinc ions have been complexed. This indicates the completion of the reaction and the total concentration of zinc in the solution can then be determined.