题干

下列实验操作中正确的是

A:蒸发操作时,应使混合物中的水分完全蒸干后,才能停止加热

B:蒸馏操作时,应向蒸馏液体中加入几块沸石,以防止暴沸

C:分液操作时,先将分液漏斗中下层液体从下口放出,再将上层液体从下口放出

D:萃取操作时,可以选用CCl4或酒精作为萃取剂从碘水中萃取碘

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答案(点此获取答案解析)

B

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阅读理解

    Bandhavgarh National Park in India is best known for its amazing setting, as well as having the highest concentration of tigers in India. In addition to tigers, there are also bears, deer, wolves, birds, etc.

    Location: In Madhya Pradesh state, almost 200 kilometers northeast of Jabalpur. The nearest village is Tala, which is the access point of the park.

    Opening Hours and Safari(打猎)Times

    Safaris operate twice a day, starting at dawn until late morning, and mid afternoon until sunset. The best time to visit the park is early in the morning or after 4 p.m. to spot the animals. the park is closed from July 1 to September 30 due to the monsoon season(季风季节).

    Bandhavgarh Zone

    Bandhavgarh is divided into three main zones: Tala (the park's best zone, with the most tigers), Magdhi (the second best zone to see tigers), and Khitauli (scenic and less visited, although tiger sighting do occur there; particularly good for birding).

    Entry Fees and Charges for Jeep Safaris

    Bandhavgarh has become expensive to visit in recent years. Entry fees have increased since October 2014. When going on a safari, separate fees must be paid for park entry and jeep hire. Entry tickets are priced per vehicle (up to six people). For 2015-16, park entry tickets cost as follows:

    Tala Zone: 2,400 rupees for Indians, 4,800 rupees for foreigners. (Up to six people)

    Other Zones: 1,200 rupees for Indians, 2,400 rupees for foreigners. (Up to six people)

    Jeep Hire

    Expect to pay about 2,200 rupees to hire a jeep, in addition to the entry cost. This can be done at the park entrance. All hotels can arrange jeep hire and tours, but at a higher rate. It's much less trouble though. Besides, unlike many national parks in India, it's possible to take private vehicles into Bandhavgarh.