问题 填空题

有下列物质:①氢氧化钠固体 ②铜丝 ③氯化氢气体 ④稀硫酸 ⑤二氧化碳气体 ⑥熔融氯化钠 ⑦碳酸钠粉末 ⑧蔗糖晶体.请用序号填空:

(1)上述状态下可导电的是______. (2)属于电解质的是______.

(3)属于非电解质的是______.

(4)上述状态下的电解质不能导电的是______.

答案

(1)能导电的物质--必须具有能自由移动的带电的微粒,金属铜中存在能自由移动的带负电的电子能导电,稀硫酸和熔融氯化钠中都有能自由移动的正负离子,也能导电,故答案为:②④⑥;

(2)电解质是在水溶液中或熔融状态下能够导电的化合物,故答案为:①⑥⑦;

(3)非电解质是在水溶液中或熔融状态下都不能能够导电的化合物,故答案为:③⑤⑧;

(4)题目中的电解质只有氢氧化钠固体、熔融氯化钠、碳酸钠粉末,氢氧化钠和碳酸钠在水溶液中或熔融状态下才能够导电,固体状态下没有能自由移动的正负离子,不能导电,故答案为:①⑦.

完形填空

A young man and an old man were waiting for a bus at a station. They sat _1__ each other. “What’s that in your bag?” asked the young man, pointing to a big bag beside the ___2__.
“Money, nothing but money,” answered the old man. The young man could ___3___ believe his own ears. “What?” he said to himself in surprise. “So much money? My God! How I __4__ to be able to get so much money!” Then he began to think about how to get the money.
The old man ___5__ tired and it seemed that he could hardly keep his eyes open. “Are you tired, sir?” asked the young man.  “Then you’d better lie down on the ___6____ and have a good rest.  Don’t worry about ___7___. I’ll wake you up in time. ”
“All right . It’s very kind of you, young man. ” The old man lay down and ___8___ he fell asleep.
The young man took the big bag gently. ___9___ when he was just going to run away , he found a corner of his fur coat (皮衣) was ___10___ the old man’s body . Several times he tried to pull it out, but he couldn’t. At last he took off his ____11____ and went away with the bag.
The young man ran out of the station as quickly as his ___12___ could carry him, he reached a place, and there he thought the old man couldn’t ___13___ him, he stopped and quickly opened the bag.
To his surprise, there was ___14___ but old newspapers in it. He hurried to the station at once. But when he got there, he found the old man was ___15____
小题1:
A.forB.onC.next toD.far from
小题2:
A.manB.stationC.driverD.corner
小题3:
A.surelyB.reallyC.nearlyD.hardly
小题4:
A.likeB.loveC.hateD.wish
小题5:
A.wasB.feltC.lookedD.became
小题6:
A.groundB.floorC.earthD.chair
小题7:
A.the bagB.the moneyC.the busD.me
小题8:
A.by and byB.at last C.at firstD.in the end
小题9:
A.SoB.AndC.ButD.Because
小题10:
A.aboveB.overC.underD.in
小题11:
A.shoesB.shirtC.coatD.cap
小题12:
A.legsB.footC.friendD.bike
小题13:
A.watchB.noticeC.findD.meet
小题14:
A.anythingB.everythingC.nothingD.something
小题15:
A.waitingB.goneC.cryingD.leaving
判断题