题干

规范的操作是实验成功的前提,实验操作正确的是(   )

A:蒸发操作时,蒸发皿必须放在石棉网上,用酒精灯外焰加热

B:取少量液体试剂时,滴管伸入试剂瓶内液体中,挤压胶头吸液

C:用试管夹夹持试管给液体加热时,需要移动试管,以防受热不均和液体冲出

D:实验结束后,剩余的试剂都应放回原试剂瓶

上一题 下一题 0.0难度 选择题 更新时间:2014-09-20 02:38:36

答案(点此获取答案解析)

C

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阅读理解

C

    Yang Hui was born in Longyan, Fujian. She grew up in a small village. She lost all her fingers and feet when she was three. She was badly burnt by accident when she went out with her grandparents. She couldn't walk and she seldom went out.

    The young girl had to learn to do everything. At first she wasn't able to use chopsticks. Her parents had to teach her for a long time. Thanks to her strong will(意志)to do everything by herself, she overcame those difficult times. Now she can look after herself. She also loves studying and she has finished the junior high school courses.

    About five years ago, Yang Hui saw someone make cross-stitch(十字绣)and she decided to learn to make it herself. As you can imagine, it's very difficult to make it without fingers. Yang Hui failed so many times. But she never gave up. And through many hours of practice, now she can use her arms to make good cross-stitch works and she is faster than other people. "One had to put great efforts into what she was doing." Yang Hui said.

    Now she is 21 years old and she is in hospital in Fujian. She continues making a 1.83-meter-long cross-stitch work with arms. She has no enough money for her operations(手术). Many kind-hearted people come to visit her and call on people to raise money for her.

    As for her future, Yang Hui said, "I hope to stand up and walk one day after operations. I want to make more money by selling cross-stitch works."

    If you want to know more about Yang Hui and help her, please call 13004982348.

(From Fuzhou News)