用如图甲所示装置探究萘熔化时温度的变化规律。请回答下列问题: (1)将装有萘的试管放入水中加热,而不是用酒精灯直接对试管加热,这样做不但能使试管受热均匀,而且萘的温度上升速度较 (选填“快”或“慢”),便于及时记录各个时刻的温度。 (2)除图甲所示实验器材外,还需要的实验器材有火柴和 。 (3)萘加热一段时间后,可看到烧杯中有“白气”冒出,“白气”是 (填序号)。 A.水蒸汽 38、(You may read the questions first)
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Plan your journey they easy way
This portable Traveler will give you directions from A to B
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Powered by 4AA batteries (not supplied).
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Everyone, young and old, enjoys
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MD 9569 Quizmaster was £19.99 now £14.99
1 In advertisement 2, the Traveler
enables us to learn__________.
A. the road conditions from London
to Oxfords
B. all the garages along the
chosen route
C. the time and speed of the
journey in Britain
D. the directions from London to
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2 In advertisement 3, the
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C. can be purchased in many
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C. who do market
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