Chromium(III) Hydroxide Precipitation

CrCl3 + 3NaOH → Cr(OH)3↓ + 3NaCl

概述

Chromium(III) chloride reacts with sodium hydroxide to form a green gelatinous precipitate of chromium(III) hydroxide (Ksp = 6.3 × 10⁻³¹). Cr(OH)₃ is amphoteric, dissolving in both excess acid and excess NaOH. In excess NaOH, it forms the green chromite ion [Cr(OH)₄]⁻.

参与者

角色 物质 系数 状态
反应物 Sodium Hydroxide NaOH 3 (aq)
产物 Sodium Chloride NaCl 3 (aq)

日常示例

The green color of some gemstones like emerald is due to chromium(III) ions, the same oxidation state that produces this green precipitate.

工业重要性

氢氧化铬(III)沉淀用于从工业废水中去除铬,尤其是来自电镀铬和鞣革过程的废水。

属性

类型
Precipitation
可逆
否
能量
放热
ΔH
-90.0 kJ/mol

相关反应

Aluminum Hydroxide Precipitation Barium Sulfate Precipitation Cadmium Sulfide Precipitation (Yellow) Calcium Phosphate Precipitation (Bone Mineral) Lead Carbonate Precipitation Magnesium Hydroxide Precipitation Copper Sulfide Precipitation Cobalt(II) Hydroxide Precipitation Mercury(II) Sulfide Precipitation (Vermilion) Iron(III) Hydroxide Precipitation

Frequently Asked Questions

What is the equation for Chromium(III) Hydroxide Precipitation?
The balanced equation is: CrCl₃ + 3NaOH → Cr(OH)₃↓ + 3NaCl.
What type of reaction is Chromium(III) Hydroxide Precipitation?
Chromium(III) Hydroxide Precipitation is a precipitation reaction.
Is Chromium(III) Hydroxide Precipitation exothermic or endothermic?
Chromium(III) Hydroxide Precipitation is exothermic (releases energy). The enthalpy change (ΔH) is -90.0 kJ/mol.