气体与管壁或者焰道墙壁之间产生摩擦等原因而产生()。
参考答案:阻力
用括号内所给单词的适当形式填空。
1. We are against _____ (chop) wood for a meal in the forest.
2. Many people in that village have got a cancer because they drank the _____ (pollute) water.
3. I am _____ (disgust) at the people that have bad manners.
4. My elder brother decided to go abroad to continue his _____ (educate).
5. The skirt is very _____ (suit) for you. You look very pretty m it.
6. Cheetahs are killed because of their beautiful _____ (spot) fur.
7. —What do you call that _____ (fur) animal?
—A chimpanzee.
8. Children like monkeys because they are _____ (play).
9. The panda is one of the _____ (endanger) animals in the world.
10. We all know that Australia is the home of _____ (kangaroo).
(2012•天津)完成下列实验所选择的装置或仪器(夹持装置已略去)正确的是( )
A.
用CCl4提取溴水中的Br2
B.
除去乙醇中的苯酚
C.
从KI和I2的固体混合物中回收I2
D.
配制100mL 0.1000mol•L-1 K2Cr2O7溶液