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|Section2= |Section3= |Section4= |Section7= |Section8= }} Lithium hydride is the inorganic compound with the formula LiH. It is a colorless solid, although commercial samples are grey. Characteristic of a salt-like, or ionic, hydride, it has a high melting point and is not soluble but reactive with all organic and protic solvents; it is soluble and non-reactive with certain molten salts such as lithium fluoride, lithium borohydride, and sodium hydride. With a molecular mass of slightly less than 8, it is the lightest ionic compound. ==Physical properties== LiH is a diamagnetic and an ionic conductor with a conductivity gradually increasing from at 443 °C to 0.18 Ω−1cm−1 at 754 °C; there is no discontinuity in this increase through the melting point.〔 The dielectric constant of LiH decreases from 13.0 (static, low frequencies) to 3.6 (visible light frequencies).〔 LiH is a soft material with a Mohs hardness of 3.5.〔 Its compressive creep (per 100 hours) rapidly increases from < 1% at 350 °C to > 100% at 475 °C meaning that LiH can't provide mechanical support when heated.〔 The thermal conductivity of LiH decreases with temperature and depends on morphology: the corresponding values are 0.125 W/(cm·K) for crystals and 0.0695 W/(cm·K) for compacts at 50 °C, and 0.036 W/(cm·K) for crystals and 0.0432 W/(cm·K) for compacts at 500 °C.〔 The linear thermal expansion coefficient is 4.2/°C at room temperature.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lithium hydride」の詳細全文を読む スポンサード リンク
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