试题与答案

【资料阅读】据中国室内装饰协会调查,甲醛污染大部分是由板材产生,家庭装修中使用的

题型:填空题

题目:

【资料阅读】据中国室内装饰协会调查,甲醛污染大部分是由板材产生,家庭装修中使用的夹芯板、地板、家具等都可能释放出甲醛。我国的国家标准检测:“El级板材相当于甲醛释放量为1.5mg/L;E0级板材的甲醛释放量为0.5mg/L。”El级与E0级最大的区别就是甲醛的释放量,E1级比E0级释放甲醛量多五分之一。目前,化学家已能从马铃薯中提取植物胶做板材的黏合剂,有效地减少了甲醛的排放。

试根据上述资料填空。

(1)已知甲醛的结构式为,则,其化学式为__________,其碳、氢和氧元素的最简质量比为__________,其含氧元素的质量分数等于_______________。

(2)资料中加点信息有误,实际上E1级比E0级释放甲醛量多了________________倍。

答案:

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