【单选题】比较取代羧酸 FCH 2 COOH(I) , ClCH 2 COOH(II) , BrCH 2 COOH(III) , ICH 2 COOH(IV) 的酸性大小是
【单选题】What is Tian Yuan's mother's advice on dealing with her problem with Lily?
A.
She believes that Lily will feel sorry for her behavior.
B.
She wants to meet Lily and say sorry for Tian Yuan.
C.
She wants Tian Yuan to apologize to Lily.
【单选题】比较取代羧酸 (I) α- 氯代苯乙酸, (II) 对氯苯乙酸, (III) 苯乙酸, (IV) β- 苯丙酸的酸性大小是( )
【单选题】在一棵二叉树上第 5 层的结点数最多为 _____ 。 ( 假设根结点的层数为 0)
【单选题】比较取代羧酸FCH 2 COOH,ClCH 2 COOH,BrCH 2 COOH,ICH 2 COOH的酸性最大的是()
【简答题】在折射率n 3 =1.52的照相机镜头表面涂有一层折射率n 2 =1.38的MgF 2 增透膜,若此仅适用于波长λ=550nm的光,则此膜的最小厚度为多少?