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【简答题】
某学校化学兴趣小组同学在学习了制取氧气这一节内容后，发现在实验室里用5%H 2 O 2 溶液加热制O 2 ，用带火星的木条检验，木条很难复燃．同学们经过认真观察，猜想其可能原因是______或______．为了验证此猜想是否正确，兴趣小组的同学经过热烈讨论，制定了实验方案并进行了实验． （1）第一组同学采取增大H 2 O 2 溶液浓度的方法，用l0%的H 2 O 2 溶液加热，结果一段时间后，用带火星的木条检验，木条复燃； （2）第二组同学从实验装置上进行了改进，效果很好（见图）． 在实验基础上，同学们经过交流讨论，得出了一些结论： ①由第一组同学的实验可得出：影响H 2 O 2 分解产生O 2 的量的多少及分解快慢的因素之一是______ ②第二组同学的实验验证了实验前同学们猜想的正确性，其中，浓硫酸的作用是______； （3）另有同学在5%的H 2 O 2 溶液中加入少量二氧化锰固体粉末，常温下，用带火星木条检验，木条复燃；此实验中二氧化锰所起的作用可能是______；有关化学方程式为：______．
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相关题目：
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查看完整题目与答案