\(KI\)
\(Pbl_2\)
When lead nitrate reacts with potassium iodide, a double displacement reaction occurs. The products formed are lead iodide (PbI$_2$) and potassium nitrate (KNO$_3$). Lead iodide is insoluble in water and forms a bright yellow precipitate. This yellow color is characteristic of solid PbI$_2$, and none of the other reactants or products are yellow.
The correct option is (C): Pbl
| Ore | Formula | ||
| A | Fe3O4 | I | Magnesite |
| B | MgCO3 | II | Magnetite |
| C | ZnS | III | Cinnabar |
| D | Hg2S | IV | Zinc Blende |