书城外语英国学生科学读本
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第58章 硫

1.Did you ever have to take a mixture of brimstone and treacle?This mixture has not a pleasant taste,but it is a useful medicine;and if it will do us good,we should not care much whether it has a nice taste or not.

2.Sulphur is the proper name of the yellow powder called brimstone.Sulphur is an element;that is,it is made of one kind of matter only.Out of a piece of sulphur no one can get anything but sulphur.

3.You can buy sulphur at the chemist’s①in three forms.First,there is milk of sulphur,which is a very fine powder;next,there is flowers of sulphur,which is a rather coarse powder;and lastly,there is roll sulphur,which is sold in solid sticks.

4.Sulphur is of a bright yellow colour.A piece of roll sulphur snaps easily when we try to bend it,so that we say it is brittle.It has neither taste nor smell when cold,but when warm it has a slight smell.

5.Some people put a stick of sulphur in the dish from which their dogs drink;but this is of no use as a medicine,for it will not dissolve in water.

①Chemist,a dealer in drugs and medicines.

6.Sulphur is a rather light solid,but it does not float in water.It burns very easily,and with a pale blue flame.As it burns it produces a gas with a nasty smell.The fumes①of burning sulphurwill bleach②straw,silk,and other things,and make them whiteand clean.These fumes are also useful for killing the germs which cause fevers③and other diseases④.

7.Let us put some bits of roll sulphur in an iron spoon,and hold the spoon over a clear fire.The sulphur soon melts into a clear yellow liquid.If we let this melted sulphur get hotter,it will become thick,and nearly black in colour.

8.With more heat still,the sulphur will become thin again;and if we then pour it into cold water,it will change into a soft brown mass almost like india-rubber.After a few days,this will become hard and yellow again.If the sulphur is made very hot indeed,it will turn into yellow sulphur vapour.

9.Sulphur is a mineral.It is found near volcanoes⑤,and musthave been brought up by them from a very great depth.It is also found in the earth joined with other elements,in the form of stony masses called ores.

10.But sulphur is not a metal.It has qualities⑥very differentfrom those of the metals.A metal conducts⑦heat well.If you put one end of a metal rod into the fire,the other end soon grows hot also.But sulphur conducts heat very badly.

11.Metals have also a lustrous or shining surface,but sulphur has no lustre.For these reasons sulphur is said to be a non-metal-that is,an element which is not a metal.

①Fumes,smoke.

②Bleach,make white.

③Fevers,illnesses causing great heat and thirst.

④Diseases,illnesses.

⑤Volcano,a mountain with an opening through which fire,steam,cinders,etc.,come from the inside of the earth.

⑥Qualities,properties;powers.

⑦Conducts,leads.

SUMMARY

Sulphur or brimstone is a mineral.It is found near volcanoes and in ores in the earth.It is of a bright yellow colour.It has neither taste nor smell when cold,but a faint smell when warm.It melts easily,and can be turned into vapour by great heat.It also burns easily,and gives off a gas with a bad smell.Its fumes will bleach straw,silk,etc.,and will also kill fever germs.Sulphur is used as a medicine.

【中文阅读】

1.小朋友,你们有没有过这样的经历,必须喝下一种“硫磺和糖蜜”的混合物?这种混合物的味道并不太好,但它是一种有用的药物,对身体有好处,所以我们也就不用在意好不好喝了。①2.有一种黄色粉末,传统上叫做“硫磺”(brimstone),它的正式名称叫“硫”(sulphur)。②硫是一种“元素”(element),也就是说,它只是一种物质构成的。从一块硫里,人们只能得到硫,得不到别的东西。

3.你可以在化学品商店里买到三种样子的硫:第一种是极细的粉末,名叫“硫磺乳”(milk of sulphur);第二种是相当粗的粉末,名叫“硫华”

(flowers of sulphur);第三种是“硫棒”(roll sulphur),是以固态棒状的形式出售的。

4.硫的颜色是浅黄色。要是想把一根硫棒折弯,它很容易就会折断,所以硫棒很“脆”。硫在低温下没有气味也没有味道,但在温暖的地方会有微弱的气味。

5.硫是一种很轻的固体,但并不能浮在水面上。硫很容易就能燃烧,燃烧的时候,会发出浅蓝色的火焰,还会散发出一种难闻的气体。③燃烧的硫磺冒出的烟,可以“漂白”稻草、丝绸和其他的物品,让它们变得又白又干净。这种烟,还能杀死那些导致发烧和其他疾病的细菌。④6.咱们把一根硫棒的一些碎屑,放进一个铁勺子里。把铁勺子举到明火上,硫很快就会熔化,变成一种清澈的黄色液体。⑤要是继续加热这种熔化的硫,它就会变得粘稠,颜色也会几乎变成黑色。⑥7.继续加热,硫会再次变稀;把它倒进冷水中,会变成一种棕色的软东西,差不多有点像天然橡胶。几天之后,这东西就会变回又硬又黄的状态。如果把硫磺加热到极高的温度,会化作黄色的硫蒸汽。⑦8.硫是一种矿物,可以在火山附近找到,显然是火山从地球深处带上来的。在地下也可以找到跟其他元素混在一起的硫磺,形态是类似石头的东西,叫做“矿石”。⑧9.但硫磺并不是金属,它的特性跟金属的特性很不一样。金属的“导热性”非常好,如果把一根金属棒的一头放到火中,另一头很快也会变热。但是硫磺的导热性却很差。

10.金属也有一种“有光泽的”或是“亮闪闪的”表面,但硫却没有光泽。所以人们把硫磺叫做“非金属”(non-metal),也就是“不是金属的元素”。

译注

①英国传统上认为硫磺和糖蜜混合起来,可以净化血液,所以经常作为一种“春季进补饮料”喂给孩子们。但是这种说法缺乏科学根据,而且硫磺是不能直接被身体吸收的。中国的读者,大概会很庆幸咱们没有这种习惯吧?

②这个名字也过时了,现在“硫”的拼写是sulfur。

③这是二氧化硫,毒性很强,是污染大气的重要成分。接触的时候要小心。

④这种漂白作用不太稳定,容易消退,而且容易导致食品和日用品中的二氧化硫含量超标,所以要严格按照国家标准使用。

⑤这时需要的温度大约是119摄氏度。

⑥颜色准确地说是“暗褐色”。变成暗褐色液体需要160摄氏度,暗褐色粘稠体则需要200-250度。

⑦变稀需要300摄氏度,变成蒸汽则需要444度。

⑧前面我们学过一种跟铅混合在一起的硫矿,还记得是什么吗?现在工业上用的硫,除了硫矿之外,有很多也来自烧煤和石油的时候释放的二氧化硫。

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