已知25 ℃、101 kPa下,下列反应C(石墨) + O2(g) === CO

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问题:

已知25 ℃、101 kPa下,下列反应C(石墨) + O2(g) === CO2(g) ,燃烧1 mol C(石墨)放热393.51 kJ。C(金刚石) + O2(g) === CO2(g),燃烧1 mol C(金刚石)放热395.41 kJ。可以得出的结论是[ ]

A.金刚石比石墨稳定

B.1 mol石墨所具有的能量比1 mol金刚石低

C.金刚石转变成石墨是物理变化

D.石墨和金刚石都是碳的同位素

考点:盖斯定律同位素
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下面说法不正确的是[ ]

A.三角形的面积一定,底和高成反比例

B.长方形的周长一定,长和宽不成比例

C.订阅《少年报》的份数和总钱数成正比例 

D.因为圆周长C= πd,所以π与d成反比例

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During the Spring Festival,my parents and some of my relatives

gave me some gift money.What should I do          小题1:the money? I had desired to buy a pair of Nike sports         (鞋)小题2:. I had also wanted to have an MP4 player of my         小题3:.With the gift    money I could a      小题4:what I wanted to buy.However, I soon   gave up the idea b      小题5:I knew I was still a student at school.Besides,my parents always lived a s      小题6:life.Their money was not         (容易)小题7:earned。Thinking of this,I decided to open a savings account at a bank the f      小题8:day.From now on, I’ll make both ends meet as a student financially         (支持)小题9: by my parents. I am sure my dream will         小题10:true one day with the money through my hard work.

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做业环境中主要的有害因素包括()。

A.热湿

B.毒

C.噪声

D.辐射

E.尘

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根据刑法规定,适用可以从轻或者减轻处罚法定情节的情形不包括是( )。

A.中止犯
B.教唆未遂的教唆犯
C.犯罪后自首的
D.犯罪分子有立功表现的

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