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问题 填空题

如图是某食品调味有限公司生产的XX牌白醋标签部分内容，请认真阅读内容。

回答下列问题：

（1）醋酸属于哪类物质？               。（填：氧化物、有机化合物、无机化合物）

（2）醋酸的摩尔质量为                 。

（3）某学校学生兴趣小组为了检验该品牌白醋中的醋酸（CH3COOH）含量，进行下列实验：取醋酸样品50.0mL，加入2mol·L-1 NaOH溶液25.0mL恰好反应。则该白醋中醋酸的物质的量浓度为                 。

答案

（1）有机化合物      （2）60 g/mol      （3）1 mol·L-1 

题目分析：根据醋酸的分子特征，醋酸属于有化合物。醋酸的摩尔质量是60g/mol。

醋酸样品50.0mL，加入2mol·L-1 NaOH溶液25.0mL恰好反应，则n(CH3COOH)=2mol·L-1×0.025L=0.05mol，则c(CH3COOH)==1mol/L。

点评：注意回答摩尔质量、物质的量浓度等问题时要带单位。

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