问题
选择题
属于同素异形体的一组物质是[ ]
A．一氧化碳和二氧化碳
B．水和双氧水
C．金刚石和石墨
D．氧气和液氧
答案
答案：C
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属于同素异形体的一组物质是[ ]
A．一氧化碳和二氧化碳
B．水和双氧水
C．金刚石和石墨
D．氧气和液氧
答案：C
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