题干

研究有机物一般经过以下几个基本步骤:分离、提纯→确定实验式→确定分子式→确定结构式,以下用于研究有机物的方法错误的是(  )

A:蒸馏常用于分离提纯液态有机混合物

B:燃烧法是研究确定有机物成分的有效方法

C:核磁共振氢谱通常用于分析有机物的相对分子质量

D:对有机物分子红外光谱图的研究有助于确定有机物分子中的官能团

上一题 下一题 0.0难度 选择题 更新时间:2019-01-01 02:09:03

答案(点此获取答案解析)

C

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阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项,并在答题卡上将该项涂黑。

    Have you got any wonderful plans for your coming summer vacation? Here are some wonderful films for you to kill time.

Away We Go

    With a baby on his way, a young couple, Burt and Verona, look at their lives and are puzzled about what they really want. So they hit the road and seek a place to call home. On their journey, they visit a handful of characters and learned a lot.

It's about taking the scenic route in life, preparing for the hope and excitement and fear of new beginnings, while never forgetting to look out of the window.

Orphan

    Esther, a bright and well-behaved child, however, is not as innocent as she appears. Soon after being taken home, the peace of her adoptive family is completely changed You want a good horror film about a child from hell Then you got one! Do not, in any cases, take children to see it.

                                                                                          500 Days of Summer

    Tom is in love with Summer from the moment he sees her. Can he accept that she simply likes him for now, not for forever The movie is about Tom wrestling with that reality. Tom remembers his love, Summer, as a series of joys and bafflements (疑惑). But Summer is just herself and he cannot have her.

    Here is a rare movie that begins by telling us how it will end and is about how the hero has no idea why.

2012

The director Roland Emmerich successfully dresses an old story with an old Mayan prediction, which is believed by many to happen in the coming 2012 and as a result, attracts millions of people into the cinema.

    It's just an entertaining Hollywood blockbuster (大片)with plenty of jokes, instead of a description of what the end of the world is really like. Don't take it too seriously!