为确定某铝热剂（含氧化铁和铝）的组成，分别进行下列实验： ①_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题计算题

为确定某铝热剂（含氧化铁和铝）的组成，分别进行下列实验：

①取21．4g样品，向其中加入足量NaOH溶液，测得生成标准状况下的气体体积为aL；

②取21．4g样品将其点燃，恰好完全反应；

③待②中反应产生物冷却后，加入足量盐酸，测得生成标状况下的气体体积为bL。

试求：

（1）样品中氧化铁和铝的物质的质量分别是多少？

（2）所得气体的体积比a：b 是多少？

答案

（1）n(Fe₂O₃)=0.1mol，n(Al)=0.2mol

（2）a:b=3:2

完形填空

完形填空 (共20小题；每小题1分，满分20分)
请认真阅读下面短文，从短文后各题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。
A group of frogs were traveling through the woods, and two of them fell into a deep pit（深坑）. All the other frogs 36 the pit. When they saw how 37 the pit was, they told the two frogs that they might be 38 .
The two frogs 39 what the other frogs were saying and 40 to jump up out of the pit with all of their physical strength. The other frogs 41 telling them to stop. Finally, one of the frogs 42 the comments, seriously considering them, and gave up. He 43 down and died.
The other frog continued to jump as 44 as he could. Once again, the crowd of frogs shouted at him to stop the 45 and just die. He jumped even harder and finally 46 it out. When he got out, the other frogs said, “Did you not 47 us?” The frog explained to them that he was 48 . He thought they were 49 him the whole time.
This story teaches two lessons: ① There is power of life and death in the 50 . An encouraging word to someone who is 51 can lift them up and help them make it through the day. ② A destructive word to someone who is down can be 52 it takes to kill them. Be 53 of what you say. Speak life to those who cross your path.
The 54 of words is great. It is sometimes hard to understand 55 an encouraging word can go such a long way. Anyone can speak words that tend to rob another of the spirit to continue in difficult times.

A．jumped over

B．keep peace with

D．gathered around

A．lived up to	B．paid attention to
C．got used to	D．pushed ahead with

D．difficultly

D．competition

C．encouraging

B．communication

D．misunderstanding

单项选择题 A1型题

中间部葡萄膜炎的特点不包括（）

A.发病迅速，视力急剧下降

B.可伴或不伴眼前段炎症

C.典型的改变是血堤样改变及周边玻璃体雪球样混浊

D.可出现周边视网膜炎症病灶

E.出现不明原因的黄斑水肿时应考虑有中间葡萄膜炎可能