纯碱（Na2CO3）属于_1类物质（填“酸”、“碱”或“盐”）．向纯碱的水溶液中滴入酚酞试液，试液变_2色，说明纯碱溶液呈_3性，其pH_47（填“=”、“＜”或“＞”）．_刷题宝

题干

纯碱（Na₂CO₃）属于____ 类物质（填“酸”、“碱”或“盐”）．向纯碱的水溶液中滴入酚酞试液，试液变____ 色，说明纯碱溶液呈____ 性，其pH____7（填“=”、“＜”或“＞”）．

上一题下一题 0.0难度选择题更新时间:2020-02-27 08:23:08

答案(点此获取答案解析）

盐,红,碱,＞

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