题干

一定量的Fe和Fe2O3的混合物投入到250 ml  2 mol/L硝酸溶液中,反应完全后,生成1.12 L NO(标况),再向反应后的溶液中加入1mol/LNaOH溶液,要使铁元素完全沉淀下来,所加入的NaOH溶液体积最少是                                        (    )

A:450 ml

B:500 ml

C:400 ml

D:不能确定

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A

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根据短文内容,从短文后的选项中选出适当的选项补全短文,并将选项的编号字母依次填入题号后横线上。
    A recent survey has shown that China is considered to be (he most indusuious nation in the world,____ .
    The survey 一with more than 8,000 people surveyed from Canada. France, Germany, India, Netherlands, the UK and the US—ranks their 'industriousness(勤奋度),which describes (he level to which a country is “hard—working, creative in producing new ideas or products”.
According to the international survey,____ , followed by workers from Germany and the US. Employees from a France are considered 10 be the laziest people in the world. German employees replied confidently to the survey, placing themselves first in the order of global industriousness French employees, on the other hand, seem to know (heir limitations (能力局限)____ .
A Germany newspaper reported that Chinese employees work on average 44.6 hours per work, ____ .
____ , Chinese employees have only ten days of paid leave on average, while German employees have twenty—five days. Industriousness Ranking: China, Germany, the US, Canada, India, the UK, Netherland, France.


A.emplyees from China get second place in the list
B.Although China has more public holidays than Germany
C.and many of those surveyed placed France in the last place
D.Chinese employees are the most industrious people in the world

E.while German employees average about 33.5hours of work per week
F.according to the research from Monster Worldwide and GFK,a German global market research institute.