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某兴趣小组同学将CO2通入氢氧化钠溶液中．无明显现象．为探究二者是否发生反应，同学们进行了以下的活动． 甲组活动： 【进行实验】 【质疑反思】小组同学认为上述实验不严谨的理由为 ． 【...
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氢氧化钠与硫酸的反应无明显现象某化学兴趣小组为证明氢氧化钠与硫酸发生了化学反应进行了如下的实验探究.
某实验小组进行了如下系列实验根据下图回答问题1写出图中仪器a的名称_____2实验室制备二氧化碳的发
化学实验常伴随明显的实验现象但氢氧化钠与硫酸反应无明显现象.为了证明氢氧化钠与硫酸确实发生了化学反应
一瓶氢氧化钠固体因不慎敞口放置了一段时间已经部分变质化学课外兴趣小组的同学决定测定该瓶氢氧化钠固体变
某兴趣小组利用废旧铝制品与氢氧化钠溶液反应制取氢气现用含有16g氢氧化钠的溶液和足量的废旧铝制品完全
某兴趣小组同学为了探究实验室中久置的氢氧化钠固体的成分进行了有关实验.请你与他们一起完成以下探究活动
化学兴趣小组的同学做中和反应实验时将稀盐酸滴入氢氧化钠溶液中看到有气泡产生是不是拿错了药品经检验确认
某兴趣小组利用废旧铝制品与氢氧化钠溶液反应制取氢气现用含有16g氢氧化钠的溶液和足量的废旧铝制品完全
氢氧化钠与硫酸的反应无明显现象某化学兴趣小组为证明氢氧化钠与硫酸发生了化学反应进行了如下的实验探究【
某同学取少量氢氧化钠溶液于试管中滴加氯化钙溶液发现无明显现象一段时间后他再次取该氢氧化钠溶液于试管中
下列有关实验现象的描述正确的是
将盐酸滴入氢氧化钠溶液中，有沉淀产生
氯化铜溶液中滴入氢氧化钠溶液，产生蓝色沉淀
四氧化三铁放入氢氧化钠溶液中，生成红褐色沉淀
将少量二氧化碳通入氢氧化钠溶液中，会产生白色沉淀
氢氧化钠与硫酸的反应无明显现象某化学兴趣小组为证明氢氧化钠与硫酸发生了化学反应进行了如下的实验探究【
某化学兴趣小组的甲乙两名同学在做完氧化铜和稀硫酸的实验后分别取反应后的溶液少许向其中滴加一定量的氢氧
下列实验中观察不到明显现象的是
氧化钙放入水中
打开盛有浓盐酸试剂瓶的瓶塞
二氧化碳气体通入氢氧化钠溶液中
将氢氧化钠溶液滴入氯化铁溶液中
某科学兴趣小组在实验室中配制了100g的氢氧化钠溶液取其中20g置于烧杯中将溶质质量分数为14.6%
氢氧化钠与硫酸的反应无明显现象某化学兴趣小组为证明氢氧化钠与硫酸发生了化学反应进行了如下的实验探究.
某兴趣小组的学生向装有100g稀硫酸的烧杯中慢慢滴入50g溶质质量分数为16%的氢氧化钠溶液假设其它
化学实验常伴随明显的实验现象但氢氧化钠与硫酸反应无明显现象为了证明氢氧化钠与硫酸确实发生了化学反应某
某兴趣小组需要10%的氢氧化钠溶液和10%的硫酸溶液进行中和反应实验1若选择40g上述氢氧化钠溶液则
下列物质间的反应中观察不到明显现象的是
稀硫酸滴入碳酸钠溶液中
将CO
2
通入氢氧化钠溶液中
硝酸银溶液滴入氯化钠溶液中
将稀硝酸滴入氢氧化铜中
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