题目

如图为实验室制取气体的常见装置。请回答 （1） 写出装置A制取氧气的化学方程式． （2） 收集一瓶氧气用于完成铁丝在氧气中燃烧的实验最好用（填序号）装置。 （3） 写出实验室制取二氧化碳的化学反应方程式． （4） 若用F装置干燥二氧化碳，瓶中应装． 答案：【1】2KMnO4 Δ__ K2MnO4+MnO2+O2↑ 【1】E 【1】CaCO3+2HCl=CaCl2+H2O+CO2↑ 【1】浓硫酸阅读下面短文，根据短文内容，从短文后各题所给的A、 B、 C、 D四个选项中，选择最佳项。There was a boy in India who was sent by his parents to a boarding school．Before being sent away this boy was the student in his class．But the boy when he attended the boarding school．His grades started ．He hated being in a group．He was all the time．And sometimes he even felt like killing himself．All of this because he felt that no one loved him．His parents started worrying about the boy．So his father decided to travel the boarding school and talk with him．They sat on the bank of the lake near the school．The father started asking him some questions about his classes, teachers and sports．After some time his dad said, “Do you know, son, I am here today?”The boy answered back, “to check my ?”“No, no” his dad replied, “I am here to tell you that you are the most important person for me．I want to see you happy．I don’t care about grades．I care about you．I care aboutyour ．YOU ARE MY CARE．”These words caused the boy’s eyes to fill with tears．He hugged his dad．They didn’t say anything to each other for a long time．Now the boy knew there was someone on this Earth who cared about him ．He the world to someone．And today this young man is in college at the top of his class and no one has ever seen him sad!【1】A. richest B. prettiest C. laziest D. brightest【2】 A. improved B. died C.changed D. lost/span>【3】A. rising B. dropping C. climbing D. throwing【4】A. worried B. careless C. lonely D. busy【5】A. around B. from C. in D. to【6】A. when B. where C. how D. why【7】A. homework B. subjects C. grades D. need【8】A. sadness B. kindness C. happiness D. darkness【9】A. safely B. successfully C. widely D. deeply【10】 A. meant B. owned C. moved D. Left