题目

向草酸(H2C2O4)溶液中逐滴加入酸性高锰酸钾溶液时,溶液褪色总是先慢后快。对其原因,某研究性学习小组结合化学反应原理提出猜想与假设,并设计了一系列实验进行探究:实验(1):在两支试管中分别加入10mL等浓度的草酸溶液,在②号试管中加入少量硫酸锰固体。然后在两支试管中分别加入5滴0.1 mol·L-1的硫酸酸化高锰酸钾溶液。现象如下(表1) ①号试管②号试管 加入药品草酸溶液 硫酸酸化高锰酸钾溶液草酸溶液 硫酸酸化高锰酸钾溶液 硫从方框中选择适当的词,并用其适当形式完成下面短文,每个词只用一次(4分钟,10分) switch, buy, download, about, send, visit, play, have, print, talk      My father  1  a computer for me as my birthday present. I’m very happy. The computer  2  a monitor, a keyboard, a mouse and a   3  . I   4   on the computer and then I   5   the websites and   6   with my friends on QQ. Now I can   7   computer games,  8  music, learn English and do other things on the computer. What   9  you? If you want to be my friend, please  10  emails to me. My email address is Xiaoxue@126. com. 1.______ 2. ______ 3. ______  4. ______ 5. ______ 6. ______ 7. ______ 8. ______ 9. ______ 10. ______
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