问题 填空题

脉搏短绌的患者按要求应该一名护士(),另一名护士(),同时测量()min。

答案

参考答案:测脉搏;听心率;1

填空题

由软锰矿制备高锰酸钾的主要反应如下:

熔融氧化  3MnO2+KClO3+6KOH3K2MnO4+KCl+3H2O

加酸歧化  3K2MnO4+2CO2=2KMnO4+MnO2↓+2K2CO3

相关物质的溶解度(293K)见下表:

 K2CO3KHCO3K2SO4KMnO4
溶解度/g11133.711.16.34
(1)在实验室进行“熔融氧化”操作时,应选用铁棒、坩埚钳和   。(填字母)

a.表面皿     b.蒸发皿     c.铁坩埚     d.泥三角

(2)加酸时不宜用硫酸的原因是   ;不宜用盐酸的原因是   

(3)采用电解法也可以实现K2MnO4的转化,2K2MnO4+2H2O2KMnO4+2KOH+H2↑。与原方法相比,电解法的优势为   

(4)草酸钠滴定法分析高锰酸钾纯度步骤如下:

Ⅰ 称取0.80 g左右的高锰酸钾产品,配成50 mL溶液。

Ⅱ 准确称取0.2014 g左右已烘干的Na2C2O4,置于锥形瓶中,加入少量蒸馏水使其溶解,再加入少量硫酸酸化。

Ⅲ 将瓶中溶液加热到75~80 ℃,趁热用Ⅰ中配制的高锰酸钾溶液滴定至终点。记录消耗高锰酸钾溶液的体积,计算得出产品纯度。

①滴定过程中反应的离子方程式为   

②达到滴定终点的标志为   

③加热温度大于90℃,部分草酸发生分解,会导致测得产品纯度   。(填“偏高”、“偏低”或“无影响”)     

④将一定量高锰酸钾溶液与酸化的草酸钠溶液混合,测得反应液中Mn2+的浓度随反应时间t的变化如图,其原因可能为   

单项选择题

Are you dreaming of taking a trip on your own Here is some advice on how to make your once-in-a-lifetime journey and how to stay safe when you get there.

Before you begin to look at places, activities and plane tickets, you must set a budget. When you search through the websites about travelling, it can be so easy to add another week here or there, or choose an extra activity. Setting a budget can avoid creating a huge bill, which starts very small.

With so many countries on this planet it is difficult to decide where to go. By narrowing down your search to voluntary work or a relaxing holiday, you can save a lot of time looking through websites.

After deciding where to go, you need to research the country. Find out when each season is. It would be disappointing if you were taking part in an outdoor-based activity and it rained most days. Look into medical information, as you may need certain medicine for certain countries. Above all, make sure you can afford to go to this country and take part in the activities you have dreamt about. Don’t raise your hopes too high before you know for certain it is within your budget.

By carrying a credit (信用) card with you at all times it is possible to stop yourself getting lost. Mobile phones are very important as well. However, do not depend completely on them, since electronic machines can break without warning. Therefore, always carry a list of emergency (紧急情况) phone numbers, names and addresses. Finally, learn a little of the language. Do not expect that the people there speak your own language. After all, you are in their country.

What does the word "budget" in Paragraph 2 mean().

A.记录

B.生意

C.预算

D.决定