题干

化学就在我们身边,它与我们的生活息息相关.

(1)下列是家庭厨房的一些常用物品:A.大米  B.食盐   C.莱籽油   D.食醋  E.铁锅  F.食品保鲜膜.从其中选择适当的物品,回答有关问题:(用宇母填写)

①主要为我们提供糖类的食品是 ____ .

②主要由合金制作的物品是____ .

(2)炒菜时,锅内热油着火,此时可用锅盖盖灭,其原理是____.

(3)在实验室小坤同学发现:盛氢氧化钠溶液的试剂瓶用橡皮塞,盛盐酸的试剂瓶用玻璃塞,对此他产生疑惑.课后査阅资料知道:玻璃中含有的少量二氧化硅(SiO2)能与氢氧化钠(NaOH)反应,生成有粘性的硅酸钠(Na2SiO3),容易将瓶和塞粘在一起,很难开启.硅酸钠(Na2SiO3)中Si的化合价为____ .

(4)一氧化碳与氢气在一定条件下,发生反应的化学方程式是:2CO+4H2X+C2H5OH 则X的化学式为 ____ .

上一题 下一题 0.0难度 选择题 更新时间:2011-03-19 09:13:22

答案(点此获取答案解析)

A,E,隔绝空气,+4,H2O

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阅读理解

    China has more than 30 intangible cultural heritage recognized by the UNESCO, including paper-cutting, the Dragon Boat Festival, Peking Opera, acupuncture(针灸)and so on. The organization adopted a decision that China's “The Twenty-Four Solar Terms” (二十四节气)should be put on the Representative List of the Intangible Cultural Heritage of Humanity in 2016 in Ethiopia.

    The Twenty-Four Solar Terms, knowledge of time and practices in agriculture, starts from the Beginning of Spring and ends with the Greater Cold, moving in cycles. It developed through the observation of the sun's annual movement in China. In ancient time, the method of tugui, earth sundial(日暑), was used to measure the shadow of the sun for determining the solar terms.

    The Twenty-Four Solar Terms came into being and developed in close relationship with Chinese agricultural production. At the initial stage of agricultural development, people began to explore the seasonal rules in the agricultural production to meet the needs in seeding, harvesting and other activities. Gradually, they formed the concept of “seed in spring, grow in summer, harvest in autumn and store in winter”. During the spring and autumn periods, the agricultural production was highly influenced by the seasonal changes, thus forming the concept of Solar Terms.

    As a traditional Chinese knowledge system of time with a history of thousands of years, the Twenty-Four Solar Terms clearly expresses the concepts of respect for nature, and harmony between man and nature. Created by Chinese ancestors, it have functioned as a complete set of weather calendar(日历)to guide the agricultural production in China. It has also been introduced into North Korea, Japan and other neighboring countries and still used in Japan. The Chinese heritage has provably influenced the people's way of thinking and behaving and will continue to be an important carrier of Chinese cultural identity.