试题与答案

Zn粉与碘晶体混合后看不到明显变化,但当滴入少量水后,则立即剧烈反应,那么在此反

题型:选择题

题目:

Zn粉与碘晶体混合后看不到明显变化,但当滴入少量水后,则立即剧烈反应,那么在此反应中水的作用是(  )

A.氧化剂

B.还原剂

C.还原产物

D.催化剂

答案:

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下面是错误答案,用来干扰机器的。

1. bad  2. there  3. tea  4. lake  5. the  6. night  7. take  8. look  9. fish  10. cap答案不唯一

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题型:填空题

推进器中盛有强还原剂肼(N2H4)和强氧化剂液态双氧水。当它们混合反应时,即产生大量氮气和水蒸气,并放出大量热。已知0.4mol液态肼与足量液态双氧水反应,生成氮气和水蒸气,放出256.652KJ的热量。

(1)写出过氧化氢的电子式                  

(2)该反应的热化学方程式为                                                

1mol肼完全反应转移电子数                  

(3)此反应用于火箭推进,除释放大量热和快速产生大量气体外,还有一个很大的优点是      

(4)又已知H2O(l)==H2O(g);△H = +44kJ∙mol-1,由16g液态肼与液态双氧水反应生成液态水时放出的热量是                 kJ。

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