题干

肼(N2H4)是一种无色油状液体,完全燃烧的反应方程式如下:N2H4+O2=X+2H2O,放出大量的热.下列有关说法不正确的是(   )

A:该反应中一定有化合价改变

B:肼中氮、氢元素质量比为1:2

C:该反应属于置换反应

D:X的化学式为N2

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B

同类题2

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       Q:My neighbor's back garden is an overgrown jungle for a few months and I believe I've got rats under my shed as a result. I have been troubled by such a bad scene for a long time.Can I make my neighbor manage her back garden?

       A:Firstly, you will need to contact a pest control company to deal with the rat problem, which could be a danger to you and your family. The pest control company will produce a report detailing the issue and give an opinion as to whether your neighbor's overgrown garden has caused the rats to run in all directions.

      If that is the case, then you should get in contact with your neighbor in an attempt to resolve the issue. You should discuss your concerns with all your heart with your neighbor and advise her of the situation and of the findings of the pest control company.

     You do not advise whether the house is rented out or perhaps your neighbor is elderly without the ability to deal with the problem personally. If your neighbor is uncooperative, then I would advise you undertake the following action.

     Get in contact with your local authority or the Department of Environment, Community and Local Government and report your concerns, particularly the pest issue immediately.You could also contact the HSE, more especially if children use the garden and are likely to come in contact with rat droppings etc, which can be dangerous to them. If the above is not successful, you should inform your lawyer and take advice. You should also document your conversations with your neighbor.

     If your house is for sale, ask your agent to prepare a report outlining the effect of the next door garden on value, but also outlining the effect on marketability and the negative impact on viewings.

Notes:

①uncooperative adj.不愿合作的,不愿配合的 ②authority n.权力,职权,官方,当局 ③marketability n.可销售性

同类题5

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                                                                                   爬树的男孩
                                                                          尼古拉斯·保罗(英国) 
        在夜深人静的时候,偷偷爬上那棵猴面包树,这是拉瓦一天中最期待的时光。可惜,美好的时光总是短暂的。仅仅只是两三分钟,耳边便会响起一声熟悉的口哨声,有人来了,他必须以最快的速度回到营房。
        “看到了什么?”刚刚躺下,安德烈便拖着瘸腿凑过来问道。拉瓦不想回答,但安德烈就是那个吹口哨的人。两人约定,拉瓦每天爬上树冠看看周围,看看远方,下来之后再把看到的新鲜事儿告诉放风人,也就是安德烈。三年了,两人还算默契,在这座死寂的集中营,每天都有人因为严厉的禁锢而自杀,他们却因为那棵猴面包树而充满希望。
         “我们就要自由了,等着吧!”
         安德烈一双粗糙的手在拉瓦头上抚摸,要不是因为拉瓦是黑人,连安德烈自己都会觉得眼前熟睡的少年就是自己的儿子。当然,拉瓦是不会明白安德烈的心情的,更不会想到,安德烈是戴高乐将军钦点的间谍。他并不是困在集中营,而是肩负特别使命潜伏在这片草原深处进行侦探。
那棵猴面包树就像一个梦想,它恰好坐落在集中营的中央。白天的时候,很多纳粹士兵坐在树底下休息,恨得拉瓦牙痒痒。只有到了晚上,他才觉得那棵树属于自己。
        可惜,连安德烈也没想到,梦想会突然破碎。那天晚上,他吹了好几次口哨,可拉瓦就是不肯下来,直到听到一阵急促的脚步声奔来,他知道,出事了。
           拉瓦毕竟是个孩子,熬不住接二连三的酷刑,便一股脑儿地全说了出来。【甲】但安德烈只是笑笑,即使两块火红的烙铁夹在他的双颊,也没吐出一个字来。
       本以为必死无疑,却没想到生机犹在。半个月后,盟军终于发起了大反攻。因为安德烈提供的精确信息,纳粹分子瞬间溃败,整座集中营安全解放。
安德烈伤得很重,但令随军医护人员奇怪的是,哭得最伤心的竟然是一个黑人男孩。毫无疑问,这个男孩就是拉瓦。在安德烈昏迷的日子里,他一刻都没有离开他的“搭档”。尽管医生开玩笑地跟他解释:“只要挂上水(打吊针),一定能起死回生,你就放心吧。”可是,拉瓦就像听不懂一样,虽然一脸惊愕,却依旧没有离开寸步的意思。
        当远处的炮声逐渐平息,安德烈终于睁开了眼睛。可是,拉瓦却不见了,几个医生都非常好奇地询问安德烈,那个黑人男孩到底是什么人,此刻又突然消失,他到底去哪了。乙安德烈点点头,良久,才吐出三个字:跟我来。
        在安德烈的带领下,一行医生再次来到集中营。顺着安德烈的手指,他们看到,那棵猴面包树的半个树冠已经不见了,树叶也是稀稀拉拉。显然,它遭炮击了,在烈日下显得奄奄一息。
        但这跟拉瓦有什么关系?随行医生面面相觑,却听安德烈一声口哨,树干后便露出了一个脑袋。他手里正拿着一个医院的吊瓶,准备往上爬。安德烈这次也不再躲在一旁放风了,而是拖着腿往前奔去,也不知是为了那棵树,还是树后的男孩。