“三鹿奶粉事件”的“元凶”是三聚氰胺,其化学式为C3H6N6.三聚氰胺常被用作化

题型:填空题

问题:

“三鹿奶粉事件”的“元凶”是三聚氰胺,其化学式为C3H6N6.三聚氰胺常被用作化工原料,微溶于水,有轻微毒性.三聚氰胺的摩尔质量是______,其中碳、氢、氮原子的个数比为______,碳、氢元素质量比为______,1molC3H6N6中约含碳原子的个数为______.因三聚氰胺的含氮量较高,所以被不法分子添加至奶制品中,以“提高”蛋白质含量,三聚氰胺中氮元素质量分数为______.(精确到0.1%)

考点:化学式的写法和意义物质组成元素的质量比物质组成元素的质量分数
题型:填空题

关于尿液分析仪的安装,下列说法中正确的是()

A.应安装在清洁、通风的地方

B.应安装在稳定的水平实验台上

C.应安装在有监视器的地方

D.仪器接地良好

E.应安装在恒温、恒湿的地方

题型:填空题

一个瓶子最多能装下500g的水,则这个瓶子能装下500g的下列哪种物质: [ ]

A.浓硫酸

B.酒精

C.煤油

D.汽油

题型:填空题

某种股票为固定成长股票,年增长率8%,今年刚分配股利为8元,无风险收益率为10%,市场上所有股票的平均收益率为18%,而该股票的β系数为1.5,则该股票的内在价值为( )元。

A.50.05

B.80.40

C.45.23

D.61.71

题型:填空题

阅读理解。

     As we all know,sleep is very important and necessary.I would love everyone to form the habits

below to have better sleep.

     Eat right meals and don't have meals within 4 hours of rest.If you eat much food an hour before

you go to bed,your body will hate you.Your body needs time to digest (消化) while you are still

awake.

     Exercise for at least________every day.Sometimes I become very angry when I hear on TV that

people just need 30minute exercise a week.That's funny.Every person should be getting 30minute

exercise daily along with a healthy diet.When you do exercises,you use energy that your body has

to recover from.Your body recovers when you are sleeping.The_more_exercises_you_do,the_faster

_you_will_fall_to_sleep.

     Turn the TV off.There are a few shows I watch still,but they will never get in my way of (妨碍)

sleep.The bedroom is only for sleeping and it is a place for rest.You'd better take the TV out of your

bedroom.

     Throw away the alarm.You should ask yourself a question: If I didn't have an alarm,at what time

would I get up? If that time is the time you need to get up,you should probably throw away the alarm.

If the time you actually get up at is much later than the time you do get up at,make great changes to

your way of life and the time when you go to sleep.No one should need an alarm.

1.What would be the best title of the passage?  (Please answer within 10 words.)

________________________________________________________________________

2.Which sentence in the passage is the closest in meaning to the following one?

It is a better way for you to put the television outside your bedroom.

________________________________________________________________________

3.Fill in the blank in Paragraph 3 with proper words.(Please answer within 5 words.)

________________________________________________________________________

4.Why will your body hate you if you eat much food an hour before you go to bed? (Please answer

within 15 words.)

________________________________________________________________________

5.Please translate the underlined part in Paragraph 3 into Chinese.

________________________________________________________________________

题型:填空题

若理论分选密度为1.39g/cm3,分配率为75%和25%时,分选密度分别为1.427g/cm3和1.323g/cm3,则不完善度为()。

A、0.245

B、0.178

C、1.223

D、0.133

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