题干

在一定条件下,使CO和O2的混合气体26 g充分反应,所得混合物在常温下跟足量的
Na2O2固体反应,结果固体增重14 g,则原混合气体中O2和CO的质量比可能是

A:9∶4

B:1∶1

C:7∶6

D:6∶7

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答案(点此获取答案解析)

D

同类题4

通读下面短文,掌握其大意,然后在各题所给的四个选项中选出一个最佳答案。
    How old does one have to give   31all of one's profits to charity? 40? 30 at  2  ?
Well, the answer in this case, is 13. Yes, Raje, a 13-year-old girl from Bombay, gives all the   3   from her small handicraft business to help out those in need.
    One day, when Raje was being 4  about the food   5 at home, her mother took her to a neighboring slum area(贫民区) where a food truck was distributing food to the underprivileged(弱势群体). Seeing children running behind the truck, unsure about   6  their next meal was coming from, Raje made up her mind to help in any way possible.
    Later that year, during Diwali, she started making and   7   small sky lantern and earned enough money to buy sweets for the kids and celebrate the festival with them. Since then, Raje has continued her initiative of spreading joy. She makes paper crafts  8  envelopes, photo frames, greeting cards, handicrafts as  9  as dolls, and uses the profits for a good cause.
    When her mother was diagnosed with breast cancer and was undergoing   10 , Raje began thinking about the cancer patients who could not  11 medical care. That year, she raised 30000 dollars for cancer patients. This Diwali, Raje will be conducting a workshop for poor kids  12 from cancer, teaching them how to make handicafts.
    Her inspiring story was shared over 1600   13  within two days on Facebook, and readers have showered her with hundreds of   14 comments. Raje,s story is certainly an  15   for everyone, it reinforces an important message-where there,s a will, there's a way!