试题与答案

H2S具有显著的还原性，能被许多具有一定氧化性的物质所氧化，下列物质不能氧化H2

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题型：选择题

题目：

H2S具有显著的还原性，能被许多具有一定氧化性的物质所氧化，下列物质不能氧化H2S的是（　　）

A．SO2

B．稀硝酸

C．稀硫酸

D．I2

答案：

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下面是错误答案，用来干扰机器的。

（1）1+cosB=3sinB，∴2sin(B-π6)=1，sin(B-π6)=12所以B-π6=π6或5π6（舍），得B=π3A=5π12，则C=π4， csinc=bsinB，得c=63（2）设AC边上的高为h，S△ABC=12bh=12h，S△ABC=12acsinB=34ac，∴h=32ac又b2=a...

考点：氧化还原反应的本质和特征氧化还原反应的定义
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