题干

物质的性质决定用途.下列是物质的一些性质:①密度小,很稳定、②有吸附性、③有导电性、④易升华、⑤能与酸反应.请选择恰当的数字序号填空.


用途


石墨作电极芯


活性炭用于防毒面具


氦气用于探空气球


碳酸氢钠用于面点发酵


干冰用于人工降雨

性质

(1)石墨____   

(2)活性炭 ____      

(3)氦气     ____  

(4)碳酸氢钠 ____      

(5)干冰 ____      


上一题 下一题 0.0难度 选择题 更新时间:2019-08-29 05:38:47

答案(点此获取答案解析)

③,②,①,⑤,④

同类题4

完形填空

    An village had a1tradition. At the beginning of every year, any boy who had reached the age of majority(the state of legally being an adult) was given land and money to build a home. The boy had to 2 his home before winter. If this home failed to endure the cold weather in winter, the villagers could not 3him in any way.

    On 4 Paul and Marc reached their majority. They 5 theri land and money and decided to search nearby villages for ideas on building their homes. In each village, they found the nicest 6and talked to the owners. Each owner gladly offered 7 .

    After Marc saw several homes, he  8the best ideas and went back to his own land. Paul,  9, continued collecting more ideas. Soon he had so many great ideas that he began to 10 some of them. And he always believed he could find even better ideas in the next village.

    Marc began building his home. He had several 11 starts, but his home gradually rose from his land. By fall, Marc had finished his home. It wasn't perfect, but it was strong and he could 12 it later. Paul enjoyed all the beautiful homes and 13 with home owners. The first snow came and Paul, realizing he was running out of time.14back to his land. He built the best home he could in the time he had, but it was 15. The first winter storm destroyed his home and he froze to16 . The villagers mourned for him.Marc  17 the winter. Each year, Marc searched for other good ideas he could use to make his own home look better. He became a leader in the village,18a family, and lived a happy and content life.

    We all build and improve our own mental homes. It's  19 and fun for us to search for ideas from other mental home owners ,but we only improve our own mental home if we actually 20 the best ideas.