【单选题】根据《中外合资经营企业法》的规定,在中外合资经营企业的注册资本中,外国合营者的投资比例一般不得低于( )。
【简答题】下列各图所示的实验原理、方法、装置或操作正确的是
【判断题】Secondary design consideration include structural stability, deformations, etc.
【单选题】Structural stability means the structure of an idiom is generally( ) .
【简答题】实验是化学研究的基础,下列各图所示的实验方法、装置或操作正确的是 ( )。
【判断题】Neutrons have essentially the same mass as protons. They contribute to the structural stability of the nucleus—if there are too many or too few, the nucleus may disintegrate by radioactive decay—but t...
【单选题】用标准浓度的盐酸滴定未知浓度的NaOH溶液,下列各操作(其他操作正确)中会造成测定结果偏低的是
C.
用蒸馏水洗净酸式滴定管后,装入标准盐酸进行滴定