<br><div><section class="_135editor" data-role="paragraph" style="font-size: medium; max-inline-size: 100%; margin: 0px; padding: 0px; border: 0px none; z-index: 0; overflow-wrap: break-word !important; outline: none 0px !important;"><section style="max-inline-size: 100%; margin: 0px; padding: 0px; -webkit-tap-highlight-color: rgba(0, 0, 0, 0); font-size: 14px; overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　答 醋酸中若含有硫酸或甲酸，一般做定量法很难分清。因此可用定性方法来检测该醋酸中是否含有硫酸和甲酸。</span></p></section><section style="max-inline-size: 100%; margin: 0px; padding: 0px; -webkit-tap-highlight-color: rgba(0, 0, 0, 0); font-size: 14px; overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　鉴别硫酸的方法是：取试样100mL,加入氯化钡5g，搅拌之，使其溶解，静置15min左右，观察试样液中有无白色沉淀，若试样中有白色沉淀，即为硫酸钡，证实含有硫酸。</span></p></section><section style="max-inline-size: 100%; margin: 0px; padding: 0px; -webkit-tap-highlight-color: rgba(0, 0, 0, 0); font-size: 14px; overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　鉴别甲酸可用氯化汞试验法定性测试。</span></p></section><section style="max-inline-size: 100%; margin: 0px; padding: 0px; -webkit-tap-highlight-color: rgba(0, 0, 0, 0); font-size: 14px; overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　其原理为：甲酸或碱金属甲酸盐，在醋酸一醋酸盐缓冲溶液中与氯化汞一同温热，将有白色晶态的氯化亚汞(甘汞)沉淀出来：</span></p></section><section style="max-inline-size: 100%; margin: 0px; padding: 0px; -webkit-tap-highlight-color: rgba(0, 0, 0, 0); font-size: 14px; text-align: center; overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><img src="http://dayaotex-img.gz.bcebos.com/article/fffspic/rzynd6z40.png" _src="http://dayaotex-img.gz.bcebos.com/article/fffspic/rzynd6z40.png" data-ratio="0.1447587354409318" data-w="601" style="max-inline-size: 100%; margin: 0px; padding: 0px; max-width: 100%; width: 444px; overflow-wrap: break-word !important; outline: none 0px !important; height: auto !important;"></p></section><section style="max-inline-size: 100%; margin: 0px; padding: 0px; -webkit-tap-highlight-color: rgba(0, 0, 0, 0); font-size: 14px; overflow-wrap: break-word !important; outline: none 0px !important;"><section style="max-inline-size: 100%; margin: 0px; padding: 0px; -webkit-tap-highlight-color: rgba(0, 0, 0, 0); overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　在下面的条件下，甚至用大量的下列酸类，亦无反应：醋酸、乙醇酸、乳酸、草酸、酒石酸、柠檬酸、苹果酸。所以推荐这个试验法，用于从羧酸与磺酸(或它们的碱金属盐类)的混合物中鉴定甲酸(甲酸盐)。</span></p></section><section style="max-inline-size: 100%; margin: 0px; padding: 0px; -webkit-tap-highlight-color: rgba(0, 0, 0, 0); overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　操作方法：取酸性的、中性的或弱碱性的待试稀溶液一滴，置一微量坩埚中，并加入10％氯化汞溶液及缓冲溶液各一滴。将混合物置烘箱内，在l00。C蒸发至干(避光)。用水一滴溶解蒸发残渣，并加入c(NH3)一0．1mol／L的氨溶液一滴，视甲酸(盐)的含量多少，将有或深或浅的黑色至灰色出现。每100mL缓冲溶液含冰醋酸lmL和醋酸钠1g。</span></p></section><section style="max-inline-size: 100%; margin: 0px; padding: 0px; -webkit-tap-highlight-color: rgba(0, 0, 0, 0); overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　该法鉴定限度：5μg甲酸。</span></p></section></section><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; overflow-wrap: break-word !important; outline: none 0px !important;"><br style="max-inline-size: 100%; margin: 0px; padding: 0px; overflow-wrap: break-word !important; outline: none 0px !important;"></p></section><section class="_135editor" data-role="paragraph" id="autoparagraph" style="font-size: medium; max-inline-size: 100%; margin: 0px; padding: 0px; border: 0px none; z-index: 0; overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; overflow-wrap: break-word !important; outline: none 0px !important;"><br style="max-inline-size: 100%; margin: 0px; padding: 0px; font-family: 微软雅黑, &quot;Microsoft YaHei&quot;, sans-serif; font-size: 17px; caret-color: rgb(255, 0, 0); overflow-wrap: break-word !important; outline: none 0px !important;"></p></section></div>