问题
选择题
石油是一种没有固定沸点的油状物，经过汽化、冷凝分离后可得到汽油、煤油等产品。由此可以判定石油属于
A．氧化物
B．纯净物
C．化合物
D．混合物
答案
答案：D
题目分析：石油中含有汽油、煤油等多种成分，属于混合物。选D。
点评：混合物是由不同种物质组成的，成分复杂；而纯净物是由一种物质组成的，成分单一。
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石油是一种没有固定沸点的油状物，经过汽化、冷凝分离后可得到汽油、煤油等产品。由此可以判定石油属于
A．氧化物
B．纯净物
C．化合物
D．混合物
答案：D
题目分析：石油中含有汽油、煤油等多种成分，属于混合物。选D。
点评：混合物是由不同种物质组成的，成分复杂；而纯净物是由一种物质组成的，成分单一。
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