问题 填空题

将一个鸡蛋洗净后,放入装有食醋的杯子中,观察到的现象 ______原因:______说明鸡蛋壳中有 ______物质.

答案

醋酸具备酸的共性,与鸡蛋壳中的碳酸盐反应会生成二氧化碳,开始附着在蛋壳表面使鸡蛋上浮,到达液面后,气体溢出,鸡蛋就有下沉.

故答案为:产生气泡,鸡蛋上下浮动(蛋壳逐渐变薄变软);上下浮动是因为碳酸钙产生的二氧化碳附着在蛋壳表面,没有上浮,就拖着鸡蛋上升了,到达液面后,气体溢出,鸡蛋就有下沉了;碳酸钙等

阅读理解

阅读理解。

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