<p><b>氟化鑭</b>是一種高熔點的離子化合物，化學式為LaF<sub>3</sub>。其Ksp為7.0×10<sup>-17</sup>。</p>

<h2><span id=".E5.88.B6.E5.A4.87"></span><span id="制备">製備</span></h2>
<p>氟化鑭可由氧化鑭和氟化氫銨反應得到：</p>
<dl><dd><span><span><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \mathrm {La_{2}O_{3}+6\ NH_{4}HF_{2}\ {\xrightarrow {300-400^{\circ }C}}\ 2\ LaF_{3}+6\ NH_{4}F+3\ H_{2}O} }">
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    <annotation encoding="application/x-tex">{\displaystyle \mathrm {La_{2}O_{3}+6\ NH_{4}HF_{2}\ {\xrightarrow {300-400^{\circ }C}}\ 2\ LaF_{3}+6\ NH_{4}F+3\ H_{2}O} }</annotation>
  </semantics></math></span></span></dd></dl><p>硝酸鑭和氟化銨反應，沉澱出氟化鑭：</p>
<dl><dd>La(NO<sub>3</sub>)<sub>3</sub> + 3 NH<sub>4</sub>F → LaF<sub>3</sub>↓ + 3 NH<sub>4</sub>NO<sub>3</sub></dd></dl><h2><span id=".E5.8F.82.E8.80.83.E6.96.87.E7.8C.AE"></span><span id="参考文献">參考文獻</span></h2>

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**氟化鑭**是一種高熔點的離子化合物，化學式為 LaF3。其 Ksp 為 7.0×10-17。

## 製備

氟化鑭可由氧化鑭和氟化氫銨反應得到：

　
: $\mathrm {La_{2}O_{3}+6\ NH_{4}HF_{2}\ {\xrightarrow {300-400^{\circ }C}}\ 2\ LaF_{3}+6\ NH_{4}F+3\ H_{2}O} $

硝酸鑭和氟化銨反應，沉澱出氟化鑭：

　
: La(NO3)3 + 3 NH4F → LaF3↓ + 3 NH4NO3

## 參考文獻
13709-38-1