题干

在一定条件下,RO3n和I可发生如下反应:RO3n +6I+6H = R+ 3I2 +3H2O,则RO3n中R元素的化合价为:               (       )

A:+1

B:+3

C:+5

D:+7

上一题 下一题 0.0难度 选择题 更新时间:2019-08-24 12:43:26

答案(点此获取答案解析)

C

同类题4

阅读以下材料:
材料一 随着资本主义的发展,富商、作坊主和银行家等更加相信个人的价值和力量,多才多艺、高雅博学之士受到人们的普遍尊重,这为文艺复兴的发生提供了深厚的物质基础和适宜的社会环境。文艺复兴运动作为一场弘扬新兴资产阶级文化的思想解放运动,极大冲击了封建神学思想的统治,为资本主义的深入发展积淀了丰富的文化养料,同时也为欧美的资产阶级革命做了文化思想方面的准备。
材料二 二十世纪初,以陈独秀为代表的先进知识分子认识到“国人精神……历经革命却黑暗依旧。……如需革新政治,必先革新国人之精神”。在这一大背景下,欧洲文艺复兴成为中国知识分子关注的对象。……此后,人文主义思想成为知识分子们反封建反传统和建设新文化的重要理论资源,为中国革命转向新的社会革命做了思想文化上的铺垫。
材料三 在新文化运动后期,……马克思列宁主义得到进一步传播,使新文化运动迅速发展成为以马克思主义为主流的思想解放运动,从而为中国转向无产阶级革命奠定了思想文化基础,为***的成立创造了条件。
请回答:
(1)根据材料一,归纳资本主义发展与文艺复兴之间的内在联系。
(2)根据材料二,分析中国先进知识分子关注欧洲文艺复兴的目的是什么?
(3)比较材料二、三,概括指出中国先进知识分子在新文化运动中传播的主要内容的变化。
(4)综合三则材料,概述思想文化运动与各国政治革命之间的关系。

同类题5

阅读理解

    We want our children to succeed, in school and, perhaps even more importantly, in life. But the paradox(悖论) is that our children can only truly succeed if they first learn how to fail. Consider the finding that world-class figure skaters fall over more often in practice than low-level figure skaters. At first sight this seems contradictory. Why are the really good skaters falling over the most?

    The reason is actually quite simple. Top skaters are constantly challenging themselves in practice, attempting jumps that stretch their limitations. This is why they fall over so often, but it is precisely why they learn so fast. Lower-level skaters have a quite different approach. They are always attempting jumps they can already do very easily, remaining within their comfort zone. This is why they don't fall over. In a superficial sense, they look successful, because they are always on their feet. The truth, however, is that by never failing, they never progress.

    What is true of skating is also true of life. James Dyson worked through 5,126 failed prototypes(原型) for his dual cyclone vacuum before coining up with the design that made his fortune. These failures were essential to the pathway of learning. As Dyson put it: “You can't develop new technology unless you test new ideas and learn when things go wrong. Failure is essential to invention.”

    In healthcare, however, things are very different. Clinicians don't like to admit to failure, partly because they have healthy egos(自我)(particularly the senior doctors) and partly because they fear litigation(诉讼). The consequence is that instead of learning from failure, healthcare often covers up failure. The direct consequence is that the same mistakes are repeated. According to the Journal of Patient Safety, 400,000 people die every year in American hospitals alone due to preventable error. Until healthcare learns to respond positively to failure, things will not improve.

    But let us return to children. One of the major mistakes in education in the 1970s was the attempt to equip children with confidence by giving them lots of successes (setting the bar very low). The consequence was that the ego of kids became bound up with success, and they became unable to take risks and collapsed as soon as they hit a proper challenge.

    We need to flip(翻转) this approach. In a complex world, failure is inevitable. It is those individuals and institutions that have the flexibility to face up to failure, learn the lessons and adapt which eventually excel(突出).