Calcium hypochlorite - Diaensosan calcium

Ca(ClO) ₂ (142.98). In addition to the anhydrous form, di-, tri-, and tetrahydrate forms are also available, but it is difficult to obtain any of these in 100% pure form. Practical bleaching powder usually contains about 50% Ca(ClO) ₂ (high-grade bleaching powder is over 70%). The pure form is obtained by reacting calcium hydroxide with hypochlorous acid or dichlorine monoxide (Cl ₂ O) and drying under reduced pressure. The anhydrous form is a colorless powder. It is relatively stable at room temperature, but decomposes rapidly above 150 °C. It is deliquescent and easily soluble in water. It exhibits strong oxidizing properties. It is used for sterilization (swimming pool water, etc.), bleaching, oxidizing agents, analytical reagents, etc. [CAS 7778-54-3]

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

Ca(ClO)₂(142.98)．無水物のほかに，二，三，四水和物も得られているが，いずれも100％ 純粋なものは得にくい．実用されるさらし粉は，普通，約50％(高度さらし粉は70％ 以上)のCa(ClO)₂を含む．純品は，水酸化カルシウムと次亜塩素酸または一酸化二塩素Cl₂Oとの反応でつくり，減圧乾燥すると得られる．無水物は無色の粉末．室温では比較的安定であるが，150 ℃ 以上では急激に分解する．潮解性で，水に易溶．強い酸化作用を示す．殺菌(プールの水など)，漂白，酸化剤，分析試薬などに用いられる．[CAS 7778-54-3]

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