题干

在150℃时使NH4HCO3分解,将所产生的气体依次通过Na2O2和浓H2SO4,则Na2O2增重a g,浓H2SO4增重b g;若将上述气体先通过浓H2SO4,则使酸液增重dg,再通过Na2O2,则使之增重c g.设气体皆完全被吸收,a、b、c、d质量由大到小的排列顺序正确的是(   )

A:d a c b

B:b c a d

C:a c b d

D:d c b a

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A

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    By the time we reach adulthood, many of us have had the good fortune to have at least one best friend. If we have1around or changed our life situation2,we may be lucky enough to have had several. The best friend relationship is often our earliest3peer relationship, and it can be a source of great warmth and4throughout our lives. The characteristics of best friendship change as we grow up and grow older, but the heart of it remains the 5. Our best friends are a warm shelter in which we feel free to be fully ourselves, to share our deepest secrets, to 6when we are overtaken by tiredness, to have a 7when there is something nice to happen in our life—a place in which we feel completely welcome to give and receive that most 8of all gifts, love.

    Most close relationships do face9from time to time, and one of the characteristics of an enduring best friendship is its ability to10the storms and to remain unbroken even as it faces changes. Our best friends are those who manage to love us through all of our11, as we do the same for them. We find ways to hug and 12the differences between us and offer love and13no matter what. We allow each other to be 14as we are at a given moment, even as we allow each other to change over time.15, best friends sometimes feel like family. We know we will stick together 16we take our individual roads.

    We may be on the phone with our best friends every day, or we may not have17with each other for a year, yet we know that our bond will be strong and18when we do19each other. This bond ties us together even when are apart and draws us delightfully back into the warm20of each other's company when our paths bring us together again.

同类题3

阅读文段,完成问题。

       有一次,他从昏迷中被一种喘息的声音惊醒了。他听到病狼喘着气,在慢慢地向他逼近。它愈来愈近,总是在向他逼近,好像经过了无穷的时间。他始终一动不动地躺在那儿,静静地等着。它已经到了他耳边,那条粗糙的干舌头正像砂纸一样地摩擦着他的两腮。他的两只手一下子伸了出来,他的指头弯得像鹰爪一样,可是抓了个空。

       狼的耐心真是可怕。人的耐心也同样可怕。

       这一天,有一半时间他都一直躺着不动,尽力和昏迷斗争,等着那个要把他吃掉,而他也希望能吃掉的东西。

       当他又一次从梦里慢慢苏醒过来的时候,觉得有条舌头在顺着他的一只手舔去。他静静地等着。狼牙轻轻地扣在他手上了,扣紧了。狼正在尽最后一点力量把牙齿咬进它等了很久的东西里面。突然,那只被咬破了的手抓住了狼的牙床。于是,慢慢地,就在狼无力地挣扎着,他的手无力地掐着的时候,他的另一只手也慢慢地摸了过去……

       五分钟之后,这个人已经把全身的重量都压在了狼的身上。他的手的力量虽然还不足以把狼掐死,可是他的脸已经紧紧地压住了狼的咽喉,嘴里已经满是狼毛。半小时后,这个人感到一小股温暖的液体慢慢流进他的喉咙。后来,这个人翻了一个身,仰面睡着了。