<p><b>錳酸鉀</b>（化學式：K<sub>2</sub>MnO<sub>4</sub>），可溶於氫氧化鉀溶液或水，水溶液呈綠色，只在強鹼性溶液中穩定，pH值降低會發生歧化。
</p>
<h2><span id=".E5.8C.96.E5.AD.A6.E5.8F.8D.E5.BA.94"></span><span id="化学反应">化學反應</span></h2>
<p>錳酸鉀可以被強氧化劑氧化：
</p>
<dl><dd><span><span><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\ce {2K2MnO4 + Cl2 -&gt; 2KMnO4 + 2KCl}}}">
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            <mtext>KMnO</mtext>
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    <annotation encoding="application/x-tex">{\displaystyle {\ce {2K2MnO4 + Cl2 -&gt; 2KMnO4 + 2KCl}}}</annotation>
  </semantics></math></span></span></dd></dl><p>此反應為工業上製備過錳酸鉀的方法之一。
</p><p>事實上，條件合適時錳酸鉀會發生歧化，具體反應在過錳酸鉀頁面有所描述
</p>
<h2><span id=".E8.A3.BD.E5.82.99"></span><span id="製備">製備</span></h2>
<p>錳酸鉀可在空氣或其他氧化劑（如KClO<sub>3</sub>、KNO<sub>3</sub>等）存在下，由MnO<sub>2</sub>和鹼金屬的氫氧化物或碳酸鹽共熔製得。例如：
</p>
<dl><dd><span><span><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\ce {3MnO2 + 6KOH + KClO3 -&gt; 3K2MnO4 + KCl + 3H2O}}}">
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            <mtext>MnO</mtext>
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              <mspace width="0pt" height="0pt" depth=".2em"></mspace>
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          <mtext>KOH</mtext>
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            <mtext>MnO</mtext>
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          <mtext>KCl</mtext>
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    <annotation encoding="application/x-tex">{\displaystyle {\ce {3MnO2 + 6KOH + KClO3 -&gt; 3K2MnO4 + KCl + 3H2O}}}</annotation>
  </semantics></math></span></span></dd></dl><p>過錳酸鉀加熱可以分解，生成錳酸鉀、二氧化錳和氧氣:
</p>
<dl><dd><span><span><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\rm {2KMnO_{4}{\xrightarrow {\triangle }}K_{2}MnO_{4}+MnO_{2}+O_{2}\uparrow }}}">
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**錳酸鉀**（化學式：K2MnO4），可溶於氫氧化鉀溶液或水，水溶液呈綠色，只在強鹼性溶液中穩定，pH 值降低會發生歧化。

## 化學反應

錳酸鉀可以被強氧化劑氧化：

　
: ${\ce {2K2MnO4 + Cl2 -> 2KMnO4 + 2KCl}}$

此反應為工業上製備過錳酸鉀的方法之一。

事實上，條件合適時錳酸鉀會發生歧化，具體反應在過錳酸鉀頁面有所描述

## 製備

錳酸鉀可在空氣或其他氧化劑（如 KClO3、KNO3 等）存在下，由 MnO2 和鹼金屬的氫氧化物或碳酸鹽共熔製得。例如：

　
: ${\ce {3MnO2 + 6KOH + KClO3 -> 3K2MnO4 + KCl + 3H2O}}$

過錳酸鉀加熱可以分解，生成錳酸鉀、二氧化錳和氧氣:

　
: ${\rm {2KMnO_{4}{\xrightarrow {\triangle }}K_{2}MnO_{4}+MnO_{2}+O_{2}\uparrow }}$
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