如图2的四幅图中,属于利用热传递改变物体内能的是( )
A:双手摩擦能发热
B:烧水时水温升高
C:锯木材料锯子发烫
D:钻木取火
①取样于试管中加足量水,充分振荡,静置后观察到试管中有白色沉淀产生;
②把①中物质进行过滤,往滤出沉淀中加过量稀硝酸,沉淀部分溶解并产生无色气体.
该粉末可能的组成情况有( )
— . Ours is much stronger than theirs.
根据表格内容,从题中所给的A、B、C、D四个选项中选出最佳答案。
Enjoy Harvesting
Want to relax yourself?
Want to experience country life?
Come and pick litchi!
Free for a taste.
Price:¥20 per kilo Dates: July 20th-July 28th
Add: Changlin village Tel:277-8688
Fitness Band on sale
Smartwatches without the watch
Monitor speed, time, distance, caloties burned, etc.
Long battery(电池)life (5 days)
¥800 (20% off for students)
Tel:289-6799
Visit Sam Mall for more information.
Ice and Snow Festival
Charming Ice Carving
Amazing World of Ice and Snow
Welcome to Fenghuang Park!
Dates: July 1st -July 25th
¥20 for each adult (half for each student)
Tel:288-6299
Super Pillow(枕头)Fight Party
Pillow Fight, a popular activity among young foreigners, has now come to Putian. It's a creative way to release(释放) pressure and stress.
Place:Putian Stadium
Time:2:30-5:00pm, June 28th
Fee:¥50 (pillow included)
Tel:275-6588
下列实验数据合理的是:①测得某石灰石样品中碳酸钙的质量分数为80.5%;②用托盘天平称取15.43gNaCl固体;③用普通温度计测得某液体温度为25.62℃;④用10mL量筒量取6.6mL水。()