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【简答题】
(14分)为研究盛装浓硫酸的铁质材料(碳素钢)与浓硫酸的反应，某学习小组进行了以下探究活动： [实验]取一铁钉放入一定体积浓硫酸中，加热，充分反应后得到溶液X并收集到气体Y。 ①甲同学认为x中除Fe 3+ 外还可能含有Fe 2+ 。若要确认其中的Fe 2+ ，用 (选填序号) KSCN溶液和氯水 b．铁粉和KSCN溶液 c．浓氨水 d．酸性：KMn0 4 溶液 ②为分析气体成分，取448mL(标准状况)气体Y通人足量溴水中，发生的反应式 为：Br 2 +SO 2 +2H 2 0====2HBr+H 2 S0 4 ，然后加入足量BaCl 2 溶液，经适当操作后得干燥 固体2．33 g [提出猜想] 分析上述实验中SO 2 的体积分数的结果，同学们认为Y中还可能含有其它气体并作如下 猜测： 猜想一：Y气体中可能含有H 2 ； 猜想二： 猜想三： [设计实验，验证猜想] 为验证以上猜想，同学们准备用下列装置设计探究实验(装置可重复使用，夹持仪器省 略)。 (1)实验装置连接次序为A→ → →F → →F (2)装置B中试剂作用是 。 (3)猜想一的理由是 (用化学方程式表示)。 (4)如果猜想一成立，预计实验现象应该是 。
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【单选题】Choose the best answer for each of the following items. – _______________. –The boy told me that he wanted to lie down. He said that his head ached and he felt sick.
A.
What’s the matter with the boy?
B.
What’s wrong with you?
C.
Are you O.K.?
【单选题】He did not regret saying what he said but felt that he_ it differently.
A.
could express
B.
would express
C.
could have expressed
D.
must have
【单选题】What he said at the meeting made Mary rather embarrassed, so he felt that he ______ differently.
A.
might express
B.
should express
C.
could have expressed
D.
must have expressed
【单选题】He said he didn’t regret telling the truth but felt that he ______ it differently.
A.
could have expressed
B.
could express
C.
must have expressed
D.
would express
【单选题】They felt so _______ when he said that to Mary
A.
confessed
B.
proposed
C.
astonished
D.
extended
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