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测定空气中氧气含量，集气瓶底部少量水的作用 铁丝燃烧实验中集气瓶底部少量水的作用 硫燃烧实验中集气瓶底部少量水的作用
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回答下列与水有关的问题利用红磷燃烧测定空气中氧气含量时集气瓶底部少量水的作用是．
规范操作室实验成功的关键下列有关试验中涉及到的操作错误的是
铁丝在氧气中燃烧；把光亮的细铁丝盘成螺旋状
做铁丝在氧气中燃烧实验时，预先在集气瓶底加少量水
用试管夹试管给液体加热时，试管口不要对着自己或旁人
测定空气中氧气的含量；红磷在氧气中燃烧熄灭后，即可观察水面上升情况
做铁丝在氧气中燃烧实验和硫在氧气中燃烧实验时集气瓶底部都加有少量的水其作用分别是什么
1硫在氧气中燃烧的实验中集气瓶底放入少量的水其目的是.2做铁丝在氧气中燃烧的实验中集气瓶底放入少量的
水在化学实验中有重要作用请回答下列实验中水的作用.1铁丝在氧气中燃烧时集气瓶底部放少量的水放水的目的
1做硫的燃烧实验时集气瓶底放有少量水溶有氢氧化钠做细铁丝在氧气中燃烧实验时集气瓶底部也放有少量水.其
下列物质在氧气中燃烧时集气瓶底部要垫少量细砂或水的是
木炭
硫粉
铁丝
红磷
做硫和细铁丝在氧气中燃烧的实验时集气瓶底部都要留少量的水请写出水的作用分别是什么
在做细铁丝在氧气中燃烧实验时集气瓶底部要放一些水在做硫在氧气中燃烧实验时集气瓶底部也要放一些水．请
做铁丝在氧气里燃烧的实验时预先在集气瓶里装少量水或细砂所起的主要作用是
防止瓶底炸裂
降低瓶内温度
增加氧气含量
吸收生成的物质
物质在空气和氧气中燃烧实验1铁丝在氧气中燃烧的实验集气瓶底部预先放入少量的水的原因是2硫在氧气中燃烧
在做铁丝和硫的燃烧实验时集气瓶底部都放少量的水各有什么作用
铁丝在氧气中燃烧的实验中下列操作及对应原因合理的是①铁丝绕成螺旋状增大铁丝的受热面积使温度更易达到铁
仅①②
仅②③
仅①③
①②③
水在科学实验中的应用很广泛在做铁丝在氧气中燃烧实验时常在集气瓶底部加少量水该实验中水的作用是
作溶剂
作反应物
作催化剂
保护集气瓶
1做硫的燃烧实验时集气瓶底放有少量水溶有氢氧化钠做细铁丝在氧气中燃烧实验时集气瓶底部也放有少量水．各
做铁丝在氧气里燃烧的实验时预先在集气瓶里装少量水或细沙所起的主要作用是
防止瓶底炸裂
降低瓶内温度
增加氧气含量
吸收生成的物质
下列物质在盛有氧气的集气瓶中燃烧集气瓶底部应放少量水或细沙的是
木炭
硫粉
铁丝
红磷
做细铁丝在氧气中燃烧的实验时细铁丝烧成螺旋状的目的是集气瓶底部装少量的水或细沙的目的是2分
如图是测定空气中氧气含量的装置.1写出红磷在空气中燃烧的文字表达式.2该实验得出的结论是.集气瓶底部
做铁丝在氧气里燃烧的实验时预先在集气瓶里装少量水或细沙其主要作用是
防止瓶底炸裂
降低瓶内温度
增加氧气含量
吸收生成的物质
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