they are sparingly soluble in alcohol and can be easily crystallised ; moreover,
the relatively high molecular weight of dinitrophenylhydrazine enables one
to obtain a reasonable amount of the derivative from small quantities of aldehyd
e.The main disadvantages of dinitrophenylhydrazine are its somewhat
leisurely action
and its sparing solubility in cold alcohol, so that if the base is employed in
alcoholic solution, unless a slight excess of aldehyde is used, it tends to crys
tallise with the hydrazone.

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※ 修改:·liuchao 于 Aug 23 10:15:58 2009 修改本文·[FROM: 219.234.148.*]
※ 来源:·水木社区 newsmth.net·[FROM: 219.234.148.*]

修改:liuchao FROM 219.234.148.*
FROM 219.234.148.*