题目内容

【题目】餐具上的油垢可以用加入洗涤剂的水洗掉，其原因是洗涤剂具有（ ）

A、氧化作用 B、乳化功能

C、催化作用 D、溶解油垢的功能

【答案】B

【解析】

试题分析：溶解和乳化过程都没有新物质生成，发生的是物理变化。氧化作用、催化作用都是在发生化学变化时才具有的，A、C错误；洗涤剂能将油污分散成很小的油滴形成乳浊液，洗涤剂具有乳化功能，B正确；洗涤剂不能将油污分散成分子形成溶液，不具有溶解的功能，错误。故选B

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