Final answer:
The chemical formula for the yellow compound formed when potassium reacts with the chromate ion is K₂Cr₂O₇, known as potassium dichromate. It dissociates in water into potassium ions and dichromate ions, forming an orange solution.
Step-by-step explanation:
The yellow compound mentioned is likely potassium dichromate, which has the chemical formula K₂Cr₂O₇. Potassium reacts with the chromate ion (CrO₄²⁻) to form this compound, which is composed of two potassium ions (K⁺) and one dichromate ion (Cr₂O₇²⁻). As a class II carcinogen, potassium dichromate is known to be a hazardous substance due to its oxidative properties and its ability to cause harm in biological systems.
Upon dissolution in water, potassium dichromate dissociates into its constituent ions as described by the equation:
- K₂Cr₂O₇(s) → 2K⁺ (aq) + Cr₂O₇²⁻ (aq)
Therefore, when interacted with potassium ions in aqueous solution, the resulting compound would be potassium dichromate, which forms a homogeneous orange solution as depicted in educational resources.