题干

下列离子组在给定条件下能否大量共存的判断正确,所发生反应的离子方程式也正确的是(   )

选项

条 件

离子组

离子共存判断及反应的离子方程式

A

滴加氨水

Na+、Al3+、Cl、NO3

不能共存,

Al3++3OH═Al(OH)3

B

pH=1的溶液

Fe2+、Al3+、SO42、MnO4

不能共存,5Fe2++MnO4+8H+

═Mn2++5Fe3++4H2O

C

由水电离出的H+浓度为1×1012 mol•L1

NH4+、Na+、NO3、Cl

一定能共存,

NH4++H2O═NH3•H2O+H+

D

通入少量SO2气体

K+、Na+、ClO、SO42

不能共存,2ClO+SO2+H2O═

2HClO+SO32

A:A  

B:B  

C:C  

D:C

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答案(点此获取答案解析)

B

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    “Educational researchers, political scientists and economists are increasingly interested in the characteristics and skills that parents, teachers and schools should foster in children to increase chances of success later in life,” said lead author Marion Spengler, PhD of the University of Tubingen.” Our research found that specific behaviors in high school have long-lasting effects for one's later life.”

    Spengler and her co-authors analyzed data collected by the American Institutes for Research from 346, 660 U. S. high school students in 1960, along with follow-up data from 81,912 of those students 11 years later and 1,952 of them 50 years later. The initial high school phase measured a variety of student behaviors and attitudes as well as personality characteristics, cognitive abilities, parental socioeconomic status and demographic(人口统计的)factors. The follow-up surveys measured overall educational attainment, income and occupational prestige(声望).

    Being a responsible student, showing an interest in school and having fewer problems with reading and writing were all significantly associated with greater educational attainment and finding a more prestigious job both 11 years and 50 years after high school. These factors were also all associated with higher income at the 50-year mark. Most effects remained even when researchers controlled parental socioeconomic status, cognitive aibility and other broad personality characteristics such as conscientiousness.

    While the findings weren't necessarily surprising, Spengler noted how reliably specific behaviors people showed in school were able to predict later success.

    Further analysis of the data suggested that much of the effect could be explained by overall educational achievements, according to Spengler.

    “Student characteristics and behaviors were rewarded in high school and led to higher educational attainment, which in turn was related to greater occupational prestige and income later in life,” she said. “This study highlights the possibility that certain behaviors at crucial periods could have long-term consequences for a person's life.”