某未知液中含有<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/bb194d413c974756908e1d0a0a690a67.png?x-oss-process=image/sharpen,200"/>或<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/f6a2cee372dc47c4812ca9b378634bee.png?x-oss-process=image/sharpen,200"/>，要简便地鉴定它们，最好加入下列试剂中的（）