问题 填空题

如图所示,是模拟大自然“雨”的形成实验, 加热烧瓶里的水,一段时间后金属盘下部出现了“雨”。

(1)汽化实验中烧瓶里的水经历的物态变化的是先______后__________。液

(2)为了使实验中的“雨下得大些”,可以在上方的金属盘里放置___________(选填“热水”或“冰块”)。

(3)实验中发现金属盘底部出现小水滴同时温度升高了,这_______(选填“能”或“不能”)说明液化需要放热。

(4)某同学还观察到烧瓶里的水沸腾时,瓶口附近出现了大量“白气”,请你判断“白气”较多的是图中的___________(选填.“①”或“②”)位置。

答案

(1)汽化 液化 (2)冰块 (3)不能 (4)①

题目分析:(1)实验中烧瓶里的水先由液态变为气态,是汽化过程,再由气态变为液态,是液化过程。(2)使实验中的“雨下得大些”,要加快水蒸气液化速度,水蒸气液化时大量放热,遇冷易液化,放置“冰块”可以达到要求。(3)金属盘底部出现小水滴同时温度升高,说明金属盘吸收了水蒸气液化时放出的热量,“能” 说明液化需要放热。(4)白气是水蒸气液化形成的,①处温度比②处低,水蒸气更易液化,①处白气更多。

单项选择题
阅读理解

As a boy,Tim was much influenced by books about the sea, but in fact by the age of fifteen he had decided to become a doctor rather than a sailor. His father was a dentist and as a result Tim had the opportunity of meeting many doctors either at home or elsewhere. When he was fourteen he was already hanging around the clinic of a local doctor where he was supposed to be helping to wrap up medicine bottles,but was actually trying to listen to the conversations taking place between the doctor and his patients in the next room.

During the war Tim served in the Navy as a surgeon(外科医生).“That was the happiest time of my life. I was dealing with very real suffering and on the whole making a success of it .”In California he taught the country people simple facts about medicine. He saw himself as a life-saver. He had proved his skills to himself and his ability to take decisions. Thus,while he was able to tell them what to do, he could feel he was serving them. After the war, he got married and chose to be a doctor in the countryside,working under an old doctor who was popular in the area,but who hated the sight of blood and believed that the secret of medicine was faith. This gave the younger man many opportunities to go on working as a life –saver.

小题1:Tim decided to become a doctor at fifteen mainly because      

A.hisfather wanted him to be so

B.his father was a surgeon himself

C.e had read many books about medicine

D.e had chances to meet many doctors through his father小题2:Which of the following is true according to the passage?

A.Tim got married to the old doctor’s daughter.

B.Tim continued working as a surgeon after the war.

C.Before the war,Tim worked as a doctor at a local clinic.

D.While working in California,Tim taught life-saving to the patients.小题3:From the passage we can infer that Tim        .

A.was sent to Europe during the war

B.worked as a surgeon during the war

C.was satisfied with his career as a surgeon.

D.decided to give up medicine for faith小题4:The passage is mainly about        .

A.Tim’s life story

B.Tim’s dream

C.Tim’s marriage

D.Tim’ s patients