论文部分内容阅读
众所周知,位于金属活动性顺序中氢左边的金属能与稀酸反应置换出氢,形成相应的盐。但从水溶液中析出的盐,往往是含结晶水的,加热含结晶水的盐不一定能得到无水盐。因此,不能认为某金属能置换稀酸中的氢,就一定能用该金属同酸反应制得相应的无水盐。例如,用单质铝和盐酸反应不能制得AlCl_3,因为从水溶液中析出的是AlCl_3·6H_2O晶体,加
It is well-known that the metal located to the left of the hydrogen in the metal-active sequence can react with dilute acids to displace hydrogen to form the corresponding salt. However, the salt precipitated from the aqueous solution often contains water of crystallization. Heating the salt containing water of crystallization does not necessarily result in the anhydrous salt. Therefore, we can not believe that a metal can replace the hydrogen in dilute acid, we can certainly use the metal with the acid reaction of the corresponding anhydrous salt. For example, with aluminum and hydrochloric acid can not be prepared AlCl_3, because the precipitation from the aqueous solution is AlCl_3 · 6H_2O crystals, plus