【单选题】【消耗次数:1】
五氧化二磷是白色雪花状晶体,有强烈的吸水性,是常用的( )。
干燥剂
还原剂
氧化剂
催化剂
参考答案:
复制
纠错
相关题目
【多选题】 干燥失重法中常用的干燥剂有
①  烧碱
②  石灰
③  硫酸
④  硅胶
⑤  五氧化二磷
【判断题】 缩醛对碱、氧化剂、还原剂等都比较稳定,但在酸性溶液中易水解为原来的醛和醇,因此,在羰基化合物与醇的加成反应中要使用干燥的HCl为催化剂。
①  正确
②  错误
【单选题】 ( )不容易发生氧化剂事故。
①  低温
②  酸碱接触
③  震动摩擦
④  接触还原剂
【简答题】 常用的变换催化剂有哪些?
【判断题】 . 催化剂的选择性是指催化剂促进主反应能力的大小。
①  正确
②  错误
【判断题】 含量低于20%的过氧化氢属于氧化剂。()
①  A、正确
②  B、错误
【判断题】 与氧化剂相比,有机过氧化物更危险。
①  A、正确
②  B、错误
【单选题】 在( )催化剂作用下,乙烯被空气中的氧直接氧化,生成环氧乙烷。
①  金属铂
②  活性铜
③  活性铁
④  活性银
【单选题】 苯烷基化生产乙苯过程中,催化剂红油中的( )是助催化剂。
① 
②  乙烯
③  三氯化铝
④  氯化氢
【单选题】 干燥苯胺不应选择下列哪种干燥剂
①  K2CO3
②  CaCl2
③  MgSO4
④  粉状NaOH
随机题目
【单选题】 No sooner had he sat down to lunch ____ there was a knock at the door.
①  when
②  that
③  as
④  than
【单选题】 When the teacher had ____through with the class, they felt very ashamed.
①  gone
②  got
③  done
④  taken
【单选题】 “Which of these two ties will you take?” “I’ll take ____to give me a change sometimes.”?
①  either ?
②  both ?
③  neither ?
④  all?
【单选题】 No one, except his two best friends ____his joy or sorrow in his life.
①  shares
②  share
③  sharing
④  to share
【单选题】 He would like to view difficulties ____ a kind of challenge.
①  with
②  on
③  of
④  as
【单选题】 As a result of the unfavorable working conditions, the project has to be put off____.
①  temporarily
②  tremendously
③  traditionally
④  typically
【单选题】 1.—Did you accept his invitation? — ____bet I did.
①  I
②  You
③  People
④  They
【单选题】 Thisbookisdesignedforlearners ____ nativelanguagesarenotChinese.
①  what
②  who
③  that
④  whose
【单选题】 I took someone elses book ____ mistake.
①  in
②  for
③  with
④  by
【单选题】 Abraham Lincoln was raised to farm work, ____ he continued until he was twenty-two.
①  since
②  as
③  which
④  that