题干

下列事实与氢键有关的是

A:水加热到很高的温度都难以分解

B:水结成冰体积膨胀,密度减小

C:CH4、SiH4、SnH4沸点随相对分子质量增大而升高

D:HF、HCl、HBr、HI的热稳定性依次减弱

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答案(点此获取答案解析)

B

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完形填空

    Angela a 28-year-old Canadian, was driving to visit friends in another city 800 kilometres away. Her kids, 5-year-old Lexi and 10-week-old Peter, were fed and the car was1 with all the necessities for a road trip: toys, milk powder and snacks.

    The long journey had begun to2Peter, who started to cry. Angela inserted a nursery rhyme CD into the stereo and hoped it would help3him down. The soft music had a4effect. In no time, both children became5. Angela's eyes 6too, for just a few seconds.

    When Lexi suddenly woke up, she found it was7. Airbags obsured (遮挡) all the windows. Lexi's neck hurt and Peter was crying loudly. She pulled the handle of the door, but the door was8. Turning onto her side, Lexi kicked at the door9it flopped (猛地打开) open.

    That's when Lexi 10 her mother in the front seat. She tried to wake her up but Angela didn't11. At that time Lexi found their car was on a steep hill and it was kept from12by a large tree.

    Her shoes had come off, but Lexi felt no13as she climbed over glass and rocks up the embankment (路堤) to the14her mother had driven off.

A driver was traveling on the highway15he saw a tiny child jumping up and down,16her arms, crying for help. He pulled over, and the child told him her mother needed help. The driver looked around but saw17. The barefoot child pointed to the destroyed car downhill. Without 18, he ran down the hill. Twenty minutes later, an19came. Angela was rushed to the hospital.

    Later that year, the Royal Canadian Humane Association awarded Lexi a Bronze Medal for20.