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根据下列装置图,按要求回答有关问题: (1)写出图中带有标号仪器的名称:① _________ 、② _________ . (2)若实验室用加热氯酸钾制取干燥的氧气,用的装置组合为 _________ (填序号),检验氧气已经收集满的方法是 _________ . (3)若实验室用过氧化氢溶液制取氧气,用的发生装置是 _________ (填序号),为了加快双氧水的分解速度,一般在试管中加入药品 _________ ,反应的化学方程式为 _________ . (4)实验室常用无水醋酸钠和碱石灰的混合固体在加热条件下制取甲烷气体,发生装置可选择 _________ (填序号).甲烷气体一般采用装置D进行收集,收集集气瓶的放置图F所示,据此可推断甲烷一定具备的物理性质是: _________ 、 _________ . (5)小准确称取7.9g纯净的高锰酸钾加热制取氧气,他在试管口放一团棉花,其作用是 _________ ;用排水法收集氧气的合适时机是 _________ ;实验结束后,他收集到氧气580mL(标准状况). 意外发现:根据计算,7.9g高锰酸钾完全分解,氧气560mL(标准状况).通过数据分析,意外发现收集到的氧气体积和理论计算的氧气体积不相符合,并且在实验中还意外发现锰酸钾能溶于水,二氧化锰不溶于水. 提出假设:取实验后的少量固体残渣再次加热,经检验又产生了氧气. 根据发现的问题和上述实验结果可以做出如下假设: 假设1:二氧化锰也可以受热分解产生氧气; 假设2:锰酸钾也可以受热分解产生氧气假设3: _________ (只填一种) 设计实验:用最初加热所得的残渣及必要的实验用品,设计了如下实验流程验证假设2.请在下面实验流程方框中的相应位置填写各步骤的实验操作名称. 请简要叙述步骤5的操作 _________ .得出结论:若观察到 _________ ,则假设2成立.
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