试题与答案

NA表示阿伏加德罗常数的值,下列说法正确的是( ) A.标准状况下,22.4L水

题型:选择题

题目:

NA表示阿伏加德罗常数的值,下列说法正确的是(  )

A.标准状况下,22.4L水所含有的分子数为NA

B.1molNa2SO4中含有Na+数为2NA

C.在常温常压下,22.4L氖气含有的分子数为NA

D.物质的量浓度为0.5mol/L的CuCl2溶液中,含有Cl-个数为NA

答案:

A、标准状况下,水为液态,无法确定物质的量,故A错误;

B、1molNa2SO4中含有2molNa+,Na+数为2NA,故B正确;

C、不是标准状况下,无法确定气体的物质的量,故C错误;

D、溶液的体积没有给出,无法确定物质的量,故D错误.

故选B.

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题型:阅读理解

阅读理解。

     The continent of Africa has a long history and a rich culture,and this is shown in traditional dress. You

 often find three colours-red, gold and green-in the clothing.The first colour stands for (象征) the blood

  of millions of people who suffered as slaves (奴隶); the second is for the rich resources (资源) of the

  African earth; and the third represents the grasslands of home.

     Because clothing has a strong social meaning, people are very careful in choosing what to wear. It

 would be a serious mistake to wear the wrong clothing, or to wear clothes in the wrong way. For

  example, in Ghana, a woman should wear her waistband (腰带) differently according to the importance

 of the social event.

     Traditional dress also tells us about everyday life. African designs are famous for loose (宽松的)

 clothing. Tile climate, with the hot sun and wide temperature ranges (变化), requires that the clothes are

  comfortable for daily life.

     Although many people wear Western clothes,particularly in the big cities in Africa,traditional African

 dress is very highly valued. This is because it has deep cultural meanings.

1. The passage is mainly about _____.

    A. the history of clothes in Africa        

    B. modern fashion styles in Africa

    C. the meanings of traditional dress in Africa  

    D. the materials used in traditional dress in Africa

2. According to the passage,red _____.

    A. represents the setting sun                  

    B. stands for the African earth

    C. is chosen because it is a bright colour        

    D. is a reminder of the sad history in Africa

3. Traditional dress should also be practical because _____.

    A. it needs to keep people dry in the rainy season  

    B. it needs to protect people from the climate

    C. people wear it in the big cities            

    D. it has deep cultural meanings

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题型:多项选择题 案例分析题

案例摘要:处方:碳酸氢钠50g,注射用水适量,全量1000ml。提示:依据《中国药典》二部及制剂规范要求。

以下有关细菌内毒素检查法的论述中,正确的是()

A.细菌内毒素国家标准品系自大肠杆菌提取精制得到的内毒素

B.试验用的器皿等,需经120℃干烤1小时

C.测得鲎试剂灵敏度(λC.在0.5~2.0λ时,可以λ为该批鲎试剂的灵敏度

D.细菌内毒素检查用水系指与灵敏度为0.03EU/ml或更高灵敏度的鲎试剂,在37℃+1℃条件下24小时不产生凝集反应的注射用水

E.供试品管一般为2支,如结果1支为(+),1支为(-),应另取2支供试品管复试,将试管从恒温器中轻轻取出,缓缓转动90°以判断结果

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