Calcium Carbonate Precipitation

CaCl2 + Na2CO3 → CaCO3↓ + 2NaCl

概述

Calcium chloride reacts with sodium carbonate to precipitate calcium carbonate. CaCO₃ has a Ksp of 3.4 × 10⁻⁹. This is the fundamental reaction behind water softening, where dissolved calcium (hardness) is removed as insoluble carbonate. The precipitate is a white powder.

参与者

角色 物质 系数 状态
反应物 Sodium Carbonate Na₂CO₃ 1 (aq)
产物 Calcium Carbonate CaCO₃ 1 (s)
产物 Sodium Chloride NaCl 2 (aq)

日常示例

Limescale buildup in kettles and pipes is calcium carbonate precipitated from hard water when heated or evaporated.

工业重要性

沉淀碳酸钙(PCC)用作造纸填料、油漆、塑料和药品。碳酸盐沉淀软水法是一项重要的工业过程。

属性

类型
Precipitation
可逆
否
能量
放热
ΔH
-13.0 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 Calcium Carbonate Precipitation?
The balanced equation is: CaCl₂ + Na₂CO₃ → CaCO₃↓ + 2NaCl.
What type of reaction is Calcium Carbonate Precipitation?
Calcium Carbonate Precipitation is a precipitation reaction.
Is Calcium Carbonate Precipitation exothermic or endothermic?
Calcium Carbonate Precipitation is exothermic (releases energy). The enthalpy change (ΔH) is -13.0 kJ/mol.