题目

Alice is a student who came to my class last year. Though she has already turned 60, Alice looks so fit and ________, with a bright smile and an enthusiastic attitude. I am Alice’s teacher in class, but I feel she is my teacher in life. For my 2-hour class every Saturday morning, Alice has to take a 3-hour round-trip on the road. But she is never ________ for class. Alice is very passionate about learning English. She often says, “Don’t ________ me as a 60-year-old. I am just a new beginner who wants to learn anything ________. You know, I am very excited to come to the class! ” So I f5．我省赣州稀土资源丰富，稀土开采工序中使用的草酸、硫酸铵等产生的大量废水严重污染农业用水和生活用水．某研究性学习小组对此展开了研究．【査阅资料】a、草酸的化学式为C2H2O4，草酸是一种无色透明的晶体，对人体有害，具有酸的通性：如能与碳酸盐反应产生二氣化碳，能与金属反应等．例如：H2C2O4+Na2CO3=Na2C2O4+CO2↑+H2O，则金属铁与草酸反应的化学方程式为H2C2O4+Fe═FeC2O4+H2↑．b．CO遇到浸有磷钼酸溶液的氯化钯黄色试纸，立即变蓝，而CO2遇该试纸不变色．c、硫酸铵在农业上可作化肥使用，在施肥时不能将它与氢氧化钙混合使用．【设计方案】草酸加热能分解生成水和气体，研究性学习小组的同学对受热分解生成的气体作如图所示的探究：【实验探究】该研究性学习小组同学通过观察实验中的现象，验证猜想．【现象和结论】请你帮助他们完成报告：步骤现象结论点燃酒精灯加热，观察装置C、D中现象装置C中黄色试纸变蓝装置D中澄清石灰水变浑浊产生的气体有CO产生的气体有CO2【讨论与反思】（1）实验中依据B装置中溶液质量变大现象可判断草酸分解生成了水．（2）根据结论，从环保角度考虑，装置中存在不足之处，正确的处理方法是在D装置导管口处点燃尾气，或把尾气收集起来．（3）写出草酸受热分解的化学方程式：H2C2O4$\frac{\underline{\;\;△\;\;}}{\;}$CO2↑+CO↑+H2O．