题干

下列实验操作正确的是(  )                                                                              

A:分液:用分液漏斗分开汽油和植物油的混合溶液

B:测pH:将pH试纸插入某溶液中,变色后与比色卡对比,读取pH

C:称量:用托盘天平准确称得(氢氧化钠固体+烧杯)总质量为25.56g

D:取量:用规格为10mL的量筒量取8.0mL液体

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答案(点此获取答案解析)

D

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完形填空

    “A bird with a broken wing will never fly as high.” I'm sure that John would agree with this saying1he felt this way almost every day in school.

    By high school, John was the most famous2in his town. He was always absent, didn't answer questions and got into 3He had failed almost every exam by the time he entered his senior year, yet was 4each year to a higher grade level. Teachers didn't want to 5 him again the following year. John was moving on, but definitely not moving 6

    I met John for the first time at a weekend leadership training program since John was one of 405 students who7At the start of the training, John was just standing 8the circle of students, against the back wall. He didn't 9 join the discussion groups. But slowly, the interactive games 10 him in.

    The ice really melted (融化) when the groups started building a list of 11and negative things that had occurred at school that year. John12 some constructive ideas on those situations. The other students in John's group 13 his comments. All of a sudden John felt like a 14 of the group, and before long he was 15 like a leader. By the end of the training, he had joined the Homeless Project team. The other students on the team were 16 with his passionate concern and ideas. They17 elected John co-chairman of the team.

    John started18at school every day and answered questions from teachers for the first time. He led a second project19300 blankets and 1,000 pairs of shoes for the homeless shelter.

A bird with a broken wing only needs20. Once healed, it can fly higher than the rest.