题干

下列实验方法错误的是( )

A:用水鉴别硝酸铵固体和氢氧化钠固体

B:加熟石灰研磨方法可以区分碳铵和磷肥

C:用带火星的木条区分空气、氧气和二氧化碳

D:精盐提纯实验中,蒸发结晶直到有大量晶体析出就停止加热

上一题 下一题 0.0难度 选择题 更新时间:2018-11-28 03:06:07

答案(点此获取答案解析)

C

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选择合适的选项补全短文。

    I still remember that summer before college.There were plans and ideas about what my college experience was going to be like, but none of them worked out as planned.____.

    Use the mental health services available to you.

    That first night at college was memorable. There was scare and homesickness. Missing things from home wasn't the only reason why I felt down. The academic pressure to succeed and the social pressure to fit in are too much for some people, which don't just happen in the freshman year.____ Close friends always guided me, which was important because talking helps—even if it's just with a friend. Don't be afraid to take that extra help.

    ____

    I had been ready to major in politics, philosophy and economics, in preparation for a law degree.Things changed.

    You meet new people and discover new interests.____ So, don't worry if you haven't figured out exactly what you're going to major in. It will likely change anyway.

    You're there to get a degree, but a little fun won't hurt.

    As time goes by, I'm not going to remember the grades I got on papers or the late nights spent studying. Instead, lifelong memories will include playing video games with my roommate at 3:00 am, or late-night runs with my friends after a night out. Apart from doing well inside the classroom, there are also internships(实习期) and other pressures. Employers might weigh internships more heavily than your GPA.____.

A. It's OK to change your mind about your major.

B. You don't want to get tired of your college life early.

C. Everyone says that college is the best four years of your life.

D. Here are the things I wish I had known before my freshman year.

E. It's normal to be a little unsure of your plans once you start taking classes.

F. Getting internships and having fun with friends are also of great importance.

G. For me, there were upsets long after the days that required a map to go anywhere.