皮皮学，免费搜题
登录
搜题
【简答题】
小雨阅读课外资料得知：氯酸钾的分解可用二氧化锰、氧化铜等物质作催化剂。于是，他对影响氯酸钾分解的因素及催化剂的催化效果产生了探究兴趣。 【提出问题】氧化铜是否比二氧化锰催化效果更好？影响氯酸钾分解速率的因素有哪些呢？ 【设计实验】小雨以生成等体积的氧气为标准，设计了下列几组实验。 序号 KClO 3 的质量 其他物质的质量 温度 氧气的体积 反应所需时间 ① 2.0g 330℃ 100mL T 1 ② 2.0g CuO 0.5g 330℃ 100mL T 2 ③ 2.0g MnO 2 0.5g 330℃ 100mL T 3 ④ 2.0g MnO 2 g 380℃ 100mL T 4 若t 1 t 2 （填“＞”、“＝”、“＜”），说明氧化铜能加快氯酸钾的分解速率。若要确定氧化铜是此反应的催化剂，还需探究反应前后，氧化铜的___________和________________不变。 你认为小雨设计实验③和实验②对比的目的是 。 实验④中MnO 2 的质量为 g，若t 3 ＞t 4 ，则化学反应快慢与温度的关系是 。 （4）写出实验④所涉及的化学方程式 。
手机使用
分享
复制链接
新浪微博
分享QQ
微信扫一扫
反馈参考答案：
举一反三
【简答题】幼儿期的运动技能主要表现为两大方面，一是手部的精细运动技能，另一是_________。
【单选题】Since the auto is the main source of travel in America and distances between major cities are far, a common way of getting around the country is by hitchhiking. Although it is not illegal, law enforce...
A.
It is a good way for children.
B.
It is illegal in America.
C.
It may involve dangers.
D.
It must be totally stopped,
【单选题】Tests Show Women Suited for Space Travel Between 1977 and 1981, three groups of American women, numbering 27 in all, between the age of 35 and 65, were given month-long tests for space travel purposes...
A.
At the end of ten years, they had to spend a further twenty days absolutely confined to bed.
B.
They were volunteers and were paid barely above the minimum wage.
C.
These tests were conducted to determine how they would respond to conditions resembling those abroad the space shuttle.
D.
They need less food and less oxygen and they stand up to radiation better.
E.
Some of them were over 65.
F.
When they were finally allowed up, the more physical active women were specially subject to pains due to a slight calcium (钙)loss.
【单选题】What's the controlling idea in the sentence? 5. There are several enjoyable ways to travel between the US and Queretaro.
A.
several enjoyable ways
B.
to travel between the US and Queretaro
【简答题】In some countries young people are encouraged to work or travel for a year between finishing high school and starting university studies. What are the advantages and disadvantages of doing this? Write...
相关题目：
参考解析：
知识点：
题目纠错 0
发布
