若以w1和w2分别表示物质的量是浓度为c1 mol/L和c2 mol/L氨水溶液的质量分数，已知2w1=w2，则下列推断正确的是（已知氨水的密度小于纯水的密度）

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若以w₁和w₂分别表示物质的量是浓度为c₁ mol/L和c₂ mol/L氨水溶液的质量分数，已知2w₁=w₂，则下列推断正确的是（）（已知氨水的密度小于纯水的密度）

A：2c₁=c₂

B：2c₂=c₁

C：c₂＞2c₁

D：c₁＜c₂＜2c₁

上一题下一题 0.0难度选择题更新时间:2016-07-05 09:43:59

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D

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Look at this photo. The girl is from Beijing. She is six years old. She is not tall and she has short black hair. She has big eyes, a small nose and a wide mouth. She is in old clothes. Now she is lost（丢失了）. Please help us find her. Our phone number is （010）8699-8886. Thanks!
阅读短文，完成下列表格关于the girl的信息，每个空格一词。

From	____	Looks
Age	Six	She is ____ and she has short ____ hair. Her eyes years are big. She has a ____ nose and a ____mouth.
Tel	（010）8699-8886

	种子数	温度	空气	水量
A组	30个	25℃	充足	足够
B组	30个	5℃	充足	不足

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