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下图是粗略测定草木灰中碳酸钾含量的部分操作，其中对应操作不规范的是（ ）
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某同学欲测定草木灰中碳酸钾的含量称取69g试样于烧杯中加入29.2g稀盐酸恰好完全反应充分反应后称得
草木灰含钾元素的主要成分是
硫酸钾
碳酸钾
硝酸钾
氯化钾
植物燃烧后的残余物称为草木灰其主要成分为碳酸钾．为测定玉米秆燃烧得到的草木灰中碳酸钾的含量某同学称取
某草木灰是农村常用的一种肥料其有效成分是碳酸钾某兴趣小组为了测定草木灰中碳酸钾的含量取现有的草木灰7
草木灰是农家肥料它的主要成分是碳酸钾某化学兴趣小组取lOOg草木灰于烧杯中不断滴入稀盐酸溶液当滴人4
草木灰是农家肥料它的主要成分是碳酸钾还有硫酸钾氯化钾等化学兴趣小组为测定某草木灰样品中的有效成分取1
下图是粗略测定草木灰中碳酸钾含量的部分操作其中对应操作不规范的是
称量
溶解
过滤
蒸发
下列钾肥中不宜施用在盐碱地的是
氯化钾
硫酸钾
草木灰
碳酸钾
碳酸钾溶于水时形成碱性物质容易使含的氮气逃到空气中散失掉而草木灰里含碳酸钾人类尿是氮肥所以人类尿跟草
会减少肥料效果
增加肥料的效用
是明智之举
是不可能的
草木灰的主要成分是
氯化钾
硫酸钾
碳酸钾
硝酸钾
古人洗衣服时一般使用浸泡的溶液其中含有碳酸钾能去污
碳酸钠
豆粉
香樟叶
草木灰
某草木灰是农村常用的一种肥料其有效成分是碳酸钾．某兴趣小组为了测定草木灰中碳酸钾的含量取现有的草木
草木灰中含有碳酸钾农民常用草木灰作为土壤的肥料同时也能改良酸性土壤．回答下列问题草木灰中含有的碳酸钾
粗略测定草木灰中碳酸钾的含量并检验钾元素的存在需经过称量溶解过滤蒸发焰色反应等操作下列图示对应的操作
称量
溶解
蒸发
焰色反应
简述从草木灰中提取碳酸钾的操作步骤
碳酸钾溶于水时形成碱性物质容易使含的氮气逃到空气中散失掉而草木灰里含碳酸钾人类尿是氮肥所以人类尿跟草
会减少肥料效果
会增加肥料的效用
是明智之举
是不可能的
某同学欲测定草木灰中碳酸钾的含量称取69g试样于烧杯中加入29.2g稀盐酸恰好完全反应充分反应后称得
草木灰的钾以碳酸钾为主约占以上
60%
70%
80%
90%
碳酸钾溶于水时形成碱性物质容易使含有氮的气体逃到空气中散失掉而草木灰里含碳酸钾人类尿是氮肥所以人类尿
会减少肥料效果
增加肥料的效用
是明智之举
是不可能的
植物燃烧后的残余物称草木灰草木灰质轻且溶于水呈碱性干时易随风而去湿时易随水而走草木灰的主要成分是碳酸
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下列说法正确的是
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