Lead Iodide Precipitation (Golden Rain)

Pb(NO3)2 + 2KI → PbI2↓ + 2KNO3

概述

Lead nitrate and potassium iodide form a bright yellow precipitate of lead iodide. When the hot mixture is cooled slowly, lead iodide crystallizes as golden shimmering plates, creating the spectacular golden rain demonstration. PbI₂ has a Ksp of 9.8 × 10⁻⁹ and is more soluble in hot water.

参与者

角色 物质 系数 状态
产物 Potassium Nitrate KNO₃ 2 (aq)

日常示例

The golden rain experiment produces one of chemistry's most visually stunning displays as golden PbI₂ crystals settle like glittering snow.

工业重要性

碘化铅（PbI₂）是效率超25%的钙钛矿太阳能电池（CH₃NH₃PbI₃）的前体材料，代表着下一代低成本高效光伏技术的发展方向，引发了全球研究热潮。

属性

类型
Precipitation
可逆
否
能量
放热
ΔH
-32.0 kJ/mol

相关反应

Aluminum Hydroxide Precipitation Barium Carbonate Precipitation Barium Sulfate Precipitation Cadmium Sulfide Precipitation (Yellow) Calcium Fluoride Precipitation (Fluorite) Calcium Phosphate Precipitation (Bone Mineral) Chromium(III) Hydroxide Precipitation Lead Carbonate Precipitation Lead Chloride Precipitation Iron(III) Hydroxide Precipitation

Frequently Asked Questions

What is the equation for Lead Iodide Precipitation (Golden Rain)?
The balanced equation is: Pb(NO₃)₂ + 2KI → PbI₂↓ + 2KNO₃.
What type of reaction is Lead Iodide Precipitation (Golden Rain)?
Lead Iodide Precipitation (Golden Rain) is a precipitation reaction.
Is Lead Iodide Precipitation (Golden Rain) exothermic or endothermic?
Lead Iodide Precipitation (Golden Rain) is exothermic (releases energy). The enthalpy change (ΔH) is -32.0 kJ/mol.