题干

碘是人体必需的微量元素之一,有“智力元素”之称。下图为碘在元素周期表中的相关信息及原子结构示意图,据此判断下列说法正确的是(  )

A:碘是一种金属元素

B:碘原子的核外有7个电子层

C:碘原子的核电荷数为53

D:碘的相对原子质量为126.9g

上一题 下一题 0.0难度 选择题 更新时间:2018-11-23 07:46:29

答案(点此获取答案解析)

C

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阅读理解

    Japan's youth are losing interest in science and as a result, threatening the nation's industrial progress. According to Japan Science and Technology Agency, young Japanese are surrounded by high-tech devices(设备), but are not interested in how they work.

    Japanese businesses have succeeded partly because they've a great many engineers. A drop in interest could lead to a decline(减少) in their numbers and quality. "In the past, the young had a big interest in science and technology," said Hirano, director of the agency's policy department.

    There are two main reasons for the problem. The first is known as "black box syndrome" of modern technology.

    Electronic devices depend on tiny silicon chips(芯片), which can only be made in big factories, whose workings can't be seen by the eyes. The devices, unlike machines of the past driven by gears and wheels, are simply boxes.

    Young Japanese, brought up on video games and at home with computers, enjoy using modern technology, but this is a passive interest and different from the interest in how things work. "You need an active interest to get interested in science. This is declining in the young," said Hirano.

    About two-thirds of Japanese in their 20s use PCs, twice the number of those in their 50s. But only 40% of those in their 20s say they are interested in news about science and technology, compared to 60% of the 50 to 60 year olds.

    "Another reason for it is that life in modern Japan is too comfortable," he said. "A wealthy society reduces people's desire to modernize and develop their country. To a degree, you can't avoid this when the fruits of science and technology are fully developed." Similarly, science in Europe and the US has also suffered a lack of interest.