下列说法中，正确的是_刷题宝

题干

下列说法中，正确的是（　　）

A：春天，冰雪消融是熔化现象，放热

B：夏天，冰冻的饮料瓶冒“冷汗”是液化现象，放热

C：秋天，大雾消散是升华现象，吸热

D：冬天，玻璃窗上的冰花是凝固现象，吸热

上一题下一题 0.0难度选择题更新时间:2016-02-18 05:29:10

答案(点此获取答案解析）

B

同类题1

“革命是历史的火车头”。英国资产阶级革命和法国大革命的共同作用是（）

同类题2

已知{a_n}的前n项和为S_n，且S_n=2a_n﹣2，则a₂=____

同类题3

下列事实可以证明一水合氨是弱电解质的是（）

①0.1mol/L的氨水可以使酚酞试液变红

②0.1mol/L的氯化铵溶液的pH约为5

③在相同条件下，氨水溶液的导电性比强碱溶液弱

④铵盐受热易分解．

同类题4

Cooking and Learning
In this E-book package, we have four e-books.

Fun with Food This fun e-book is filled with exercises --- photo tests, word exams, riddle games coloring pages and exercises on learning more about food.	Kids Food Science Experiments Learn more about science and cooking with these food science experiments and instructions for kids.
Food Facts E-Book To go with the kids cooking lessons e-book, we've put our food facts into one e-book. Each part is easy to print off. You can keep it in the kitchen and teach kids facts about the food we eat. The Food Facts E-Book has over 60 pages.	Kids Cooking Lessons E-Book We've brought all our kids cooking lessons together into one easy e-book. We have a unit for each age group. This e-book is just planned to help you with cooking experience in the kitchen. If you'd like our lessons in e-book form with some learning exercises and other things, then this e-book is for you.

同类题5

若正数x，y满足x²+3xy﹣1=0，则x+y的最小值是（）

小学学科试题库

初中学科试题库

高中学科试题库