مرکوری II آیوداید رد

Mercury(II) iodide red is a bright red crystalline inorganic compound known for its thermochromic properties and historical use in medicine and chemical analysis.

🏭⚗️ Production
It is typically prepared by reacting aqueous solutions of mercury(II) chloride with potassium iodide or directly combining elemental mercury with iodine, resulting in the precipitation of red mercury(II) iodide crystals.

🔬 Properties
The chemical formula is HgI₂ with a molar mass of approximately 454.39 g/mol. It appears as a bright red crystalline solid that exhibits thermochromism, turning yellow when heated above around 126 °C and reverting to red upon cooling. It is practically insoluble in water, slightly soluble in alcohol and ether, and decomposes at high temperatures without melting under normal pressure.

🧪 Applications
Mercury(II) iodide red is used in thermochromic applications, as a reference material in analytical chemistry, and in laboratory demonstrations due to its vivid color change with temperature. It was once used in antiseptic and dermatological preparations, but such uses have declined due to its toxicity.

⚠️ Safety
This compound is highly toxic and hazardous to human health and the environment. It can cause severe damage to the kidneys, nervous system, and other organs if inhaled, ingested, or absorbed through the skin. Handling requires strict safety measures including gloves, goggles, and the use of a fume hood. It must be stored in a tightly sealed container, in a cool, dry place, away from light and incompatible substances.