题干

某淡黄色的颗粒状固体,其化学性质比较活泼,在通常状况下能跟许多物质发生化学反应.例如:它与CO2反应时,只生成了Na2CO3和O2,它与稀盐酸反应时,只生成了NaCl、H2O和O2.上课时,老师做了如下实验:

a.取少量的淡黄色的颗粒状固体投入到盛有少量水的试管中,可观察到产生了一种无色无味的气体;

b.再向试管中滴加几滴酚酞试液,可观察到烧杯中溶液变红.

根据实验现象,回答下列问题:

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同类题1

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    “We haven't found anything that we can't recycle!”

    Cigarette ends are everywhere—littering our streets and beaches—and for decades they've been thought of as“unrecyclable”. But a New Jerseybased company, called TerraCycle, has taken on the challenge, and has come up with a way to recycle millions of cigarette ends and turn them into industrial plastic products. Its aim is to recycle things that people normally consider impossible to reuse.

    Obviously it would be even better for the environment if everyone just stopped smoking, but the statistics show that although there has been an increase in anti-smoking ads and messaging, between 2000 and 2014, global sales of cigarettes increased by 8 percent, and a whole lot of those cigarette ends are ending up as trash. Since most of our litter eventually ends up in waterways, cigarette ends can surely pollute the surrounding environment. “It only takes a single cigarette end to pollute a liter of water, ” TerraCycle founder, Tom Szaky, said. “Animals can also mistake littered cigarette ends for food.”

    So how do you go about turning all those poisonous ends into something useful? TerraCycle does this by first breaking them down into separate parts. They mix the remaining materials, such as the tobacco and the paper, with other kinds of rubbish; and use it on non-agricultural land, such as golf courses. The filters (过滤嘴) are a little harder. To recycle these, TerraCycle first makes them clean and cuts them into small pieces, and then combines them with other recycled materials, making them into liquid for industrial plastic products.

    They're now also expanding their recycling offerings to the rest of the 80 percent of household waste that currently can't be recycled, such as chocolate packaging, pens, and mobile phones. The goal is to use the latest research to find a way to stop so much waste ending up in landfill (垃圾填埋), and then get companies to provide money for the process. And so far, it's working.

    “We haven't found anything that we can't recycle,”communications director of Terra Cycle, Albe Zakes, said. “But with the amount and variety of packaging and litter in the world, we are always looking for new waste streams to address.”

同类题5

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娘从乡下来

万吉星

    ①娘从乡下来。穿双廉价的平底鞋,站在小区三十多层的高楼下,左手提个褪了色的帆布包,右手搭在额头上,尽量把头往后仰,眯着眼,才勉强看到了头顶上支离破碎的天空和几缕漏网的阳光。娘揉了揉有些混浊的眼睛,我看到了一丝无奈与迷茫。

    ②娘是农村人,是个永远无法融入城市生活的农村人。但为了替我照看孩子,她迫不得已离开那片生活了六十多年的土地,来到了陌生的昆明。

    ③娘不会跳广场舞,坐公交也会晕车,她只敢去菜市场和孙子幼儿园那两条街,远了怕迷路回不来,她和小区里的退休老太永远聊不到一块儿,她听不懂CPI是什么东西,只知道菜市场里白菜都要一块多钱一斤,说太贵了,要是在老家田边地角随便种两块,一年到头都吃不完,因此她在这个城市没有一个朋友。

    ④我与妻都忙于工作,早出晚归,谁都没有注意到一个农村老人在这个城市的孤单与苦闷。有一天下午,我正在开会,突然接到孩子幼儿园老师打来的电话,说放学十多分钟了,其他孩子都接完了,只剩我女儿没人接。放下电话,我急忙打娘的电话,响了半天她才接,电话一接通,我就不耐烦地吼道:“妈,你怎么搞的,现在还不去接孩子?别的早就接完了。”说完这话,我才听到手机里传来扑哧扑哧的喘气声,娘一边喘着粗气,一边像个做错事的孩子,上气不接下气地说:“我的手表……不知怎么……停了,刚才看电视……才发现……时间过了,不怕……我跑着去……再过四五分钟……就到了。”我的眼睛一下子就模糊了。

    ⑤我仿佛看到:一个患有关节炎的农村老太,一瘸一拐地奔跑在昆明的街头,嘴里喘着粗气,额头上布满汗珠却来不及用手擦去,一脸的自责和内疚。

    ⑥就这样,娘默默地在这个陌生的城市里为孩子们坚守着,从不在我们面前叫一声苦和累。每天接完孩子回家吃过晚饭,她便早早地回到她的小屋里休息了,但我知道她每天晚上都失眠,天不亮就起来了。渐渐的,娘的话越来越少,甚至一整天都不怎么说话。有一天中午我在单位食堂吃完饭,回家拿一份材料,打开家门,娘一个人静静地坐在有些昏暗的客厅里,我问她怎么不开电视看,她说,看多了眼睛疼,不想看。我说那出去走走吧,她说脚疼,院子里又没个朋友,街上车多人多,心烦。

    ⑦看着面容有些憔悴的娘,满头的青丝有一半变成了白发,粗糙的双手不停地揉着有些肿胀的膝盖,每次要站起来,都得用两只手撑住膝盖,手脚一起用力,这时,我听见了骨节咯吱咯吱的声响。我在娘的身旁坐下,拉过娘的手,多少年了,我还是第一次这样握着娘的手。这是一双什么样的手啊:粗糙如锉一般,指关节已经肿大变形,手背上爬满了一条条蚯蚓似的青筋。望着这双抚育我长大的手,我的眼泪再一次在眼眶里打转。

    ⑧那一夜,我失眠了,我真正理解了娘对土地的眷念和对父亲的思念。少时夫妻老来伴,她需要的不是这个繁华的城市和衣柜里我为她买来的名牌服装,而是与父亲在农村的吵吵闹闹中度过快乐的晚年。与妻商量,决定送她回到农村老家。第二天,我把想法和娘一说,我明显感觉到她的眼里闪过一丝惊喜,但随即又忧心忡忡地说:“我走了孩子谁来带?请个保姆我和你爸都不放心。”我故作轻松地安慰她:“不用请保姆,我现在工作轻闲得很,自己带得过来。”娘的眉梢舒展开来,那丝惊喜又重新回来了。她说:“那我先回去一段时间,如果你们忙不过来了,我再来帮你们带。”

    ⑨一整天,娘一反往日的闷闷不乐,开心地忙着收拾家务,把所有的垃圾倒得一干二净,把她的衣物叠得整整齐齐的放进旅行包里。我去长途汽车客运站给她买了回家的车票,晚上我拿车票给她的时候,同时给了她两千元钱,让她带回家用,车票她拿着了,钱却说什么都不要,说家里有,就这样推来挡去四五个回合,她把钱收下了。第二天早上,我送她到客运站,车临开动时,她把头伸出车窗外,对我说:“钱我压在枕头下面了,我和你爸用不了多少钱,你们在城里开销大,自己省着点用。”

    ⑩车开走了,天空下起了小雨,我分不清脸上流淌的是雨水还是泪水。

(选自《散文百家》2016年第10期,有删改)