【单选题】采用紫外-可见分光光度法测定蔬菜中NO2-含量,样品的提取液为黄绿色,显色后生成红色产物(显色剂无色),于540nm处测定吸光度。测定样品时应选择的参比溶液是
【简答题】international finance
【单选题】分光光度法测量条件的选择:采用紫外 - 可见分光光度法测定蔬菜中 NO2- 的含量,试液提取液为黄色, NO2- 与无色的显色剂显色后生成红色产物,与 540nm 处测定其吸光度。应选取的参比溶液是
【单选题】Unit 08-6.mp3: What's wrong with the consignment?
A.
It was damaged seriously
B.
The loss of breakage was 30%
【简答题】列竖式计算.(打“☆”要验算) ☆59÷4= 83÷6= 80÷5= ☆76÷7= 73÷9= ☆65÷7= ☆43÷5= 48÷6= 87÷3= ☆76÷4= 49÷3=
【单选题】Unit 6-3.mp3: What will be used in the cargo for packing?