题干

下列物质的用途,主要利用其化学性质的是( )

A:活性炭可除去冰箱中的异味

B:干冰用作人工降雨

C:氮气用作焊接金属的保护气

D:汽油可用于擦拭衣物上的油污

上一题 下一题 0.0难度 选择题 更新时间:2012-07-24 09:40:08

答案(点此获取答案解析)

C

同类题1

决定社会走向,影响发展进程的,是历史的合力。阅读材料,回答问题。

材料一:20世纪40年代后半期的中国,几乎每年都有重大事情发生。学者金冲及独具慧眼从1947年入手,写成《转折年代》。该著作以近乎白描的手法再现了1947年的中国社会面貌:

    有一份杂志刊载了一幅中美贸易的漫画,画的是长嘴鹳在一只长颈瓶里喝水,对蹲在旁边的猫说:我们是平等的,都可以自由地在这瓶里喝水;1月至8月,天津歇业工厂竟达132家,尚未宣告歇业的厂家,也多坐待油尽灯干。上海最大的纺织厂申新各厂开工纱机,尚不足抗战前1936年57万锭之数;晋西北山地农民许多穷困及破产,虽然有些地方农民已分得若干山地,但非常零碎,没有系统、普遍和彻底。目前的任务就是要有计划的去组织这样一个群众运动,并正确地把这个运动领导到底。

——摘编自《转折年代——中国的1947年》

材料二:1947年12月,***饱含激情地说:“人民解放军的主力已经打到国民党统治区域里去了。……这是一个历史的转折点……是一百多年来帝国主义在中国的统治由发展到消灭的转折点。”学者陈旭麓认为,***的话“富有历史感地把新民主主义的胜利,看成整个民主革命的胜利。辛亥革命是旧民主主义革命,但它的事业在北伐战争中得到了延伸,在解放战争中得到了最后的胜利。”

——摘自***《目前形势和我们的任务》、陈旭麓《近代中国社会的新陈代谢》

同类题2

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Ways to protect cell phones from damage

    While people use cell phones frequently, very few take the necessary measures to prevent damage. ____ Here are some simple ways for you to protect your cell phone from damage.

Keep cell phones out of the rain

    If you must talk on the phone while it's raining, try to move indoors.  ____ Otherwise, you may have trouble with the numbers or the cell phone speaker. Imagine dialing (拨打) one number and getting different results.

____

    Many people like to put their cell phones in the pants or jeans pocket. However, storing a cell phone there will put it at risk of damage. You may forget that it is still in your pocket and just sit on the cell phone. As a result, your cell phone screen will get damaged.

Do not handle cell phones while eating

    ____ This is especially true for those times when you are eating messy things and get the ingredients on your hands. One accident can cause lots of damage for your cell phone.

Get a protective cell phone case

    There are many kinds of cases available on the market. ____ It will provide a protective cushion (垫子) that may save you from paying money to fix or buy a new phone.

A. Do not put cell phones in your pocket

B. Do not throw cell phones onto hard surfaces

C. Many people often talk on the phone in the rain.

D. You can also cover the phone up with your hand.

E. Just choose one that fits the size of your cell phone.

F. One mistake may end up costing you more money.

G. Food and drinks should not be near your cell phones.