【简答题】sp 3 、 sp 2 、 sp 杂化轨道的夹角分别为 、 和 。
【判断题】卡诺图中逻辑相邻的最小项,在几何位置不一定相邻。
【判断题】在卡诺图中,几何相邻的最小项一定逻辑相邻。
【单选题】有关杂化轨道的说法不正确的是( )
A.
杂化前后的轨道数不变,但轨道的形状发生了改变
B.
sp 3 、sp 2 、sp杂化轨道的夹角分别为109°28′、120°、180°
C.
部分四面体形、三角锥形、V形分子的结构可以用sp 3 杂化轨道解释
【判断题】在卡诺图中,逻辑相邻的最小项也一定几何相邻。
【单选题】关于电力拖动起货机的电动机与控制设备,说法错误的是______。
D.
起货机的制动环节一般只采取电气制动,不使用电磁制动器
【单选题】Many a specialist_____ looking forward to attending that conference now and they______ plants in the last two years to prepare for it.
A.
is; have been studying
C.
are; have been studying
【单选题】Direction: You are required to complete the following sentence by deciding on the most appropriate word or words from the 4 choices marked A, B, C, and D. Many a specialist looking forward to attendin...
A.
is; have been studying
B.
are; have been studying
【简答题】The specialist is______. THERE ARE A GREAT MANY CAREERS IN WHICH THE INCREASING EMPHASIS IS ON SPECIALIZATIO N. YOU FIND THESE CAREERS IN ENGINEERING, IN PRODUCTION, IN STATISTICAL WORK, AND IN TEACHI...