Amalgam (chemistry) organic synthesis (e.g., for the Clemmensen reduction). It is the reducing agent in the Jones reductor, used in analytical chemistry. Formerly the zinc plates of dry batteries were amalgamated with a little mercury to prevent deterioration in storage. It is a binary solution (liquid-solid) of mercury and zinc. For the alkali metals, amalgamation is exothermic, and distinct chemical forms can be identified, such as KHg and KHg. KHg is a gold-coloured compound with a melting point of 178 °C, and KHg a silver-coloured compound with a melting point of 278 °C. These amalgams are very sensitive to air and water,
What Is History? to suit their facts, and takes part in a dialogue between past and present. Summing up his argument, Carr puts forward his own answer to the question of "what is history?", remarking that "it is a continuous process of interaction between the historian and his facts, an unending dialogue between the past and the present." it is precisely for matters of this kind that the historian is entitled to rely on what have been called the auxiliary sciences of history In his second chapter, Carr focuses on the influence that society plays on forming the approach of the historian and