问题 选择题

已知某反应aA(g) +bB(g) cC(g)  ΔH ="Q" 在密闭容器中进行,在不同温度(T1 和T2 )及压强(P1 和P2 )下,混合气体中B的质量分数w(B)与反应时间(t)的关系如图所示,下列判断正确的是

A.T1<T2, P1<P2 ,a+b>c ,Q>0

B.T1>T2 ,P1<P2 ,a+b<c ,Q<0

C.T1<T2 ,P1>P2 ,a+b<c, Q>0

D.  T1<T2 ,P1>P2 ,a+b>c ,Q<0

答案

答案:B

题目分析:由图象可知,温度为T1时,根据到达平衡的时间可知P2>P1,且压强越大,B的含量越高,说明压强增大平衡向逆反应方向移动,故正反应为气体体积增大的反应,即a+b<c;压强为P2时,根据到达平衡的时间可知T1>T2,且温度越高,B的含量越高,说明温度升高平衡向逆反应方向移动,则正反应为放热反应,即Q<0,故B项正确。

阅读理解

From:Li-Hong @ net. cn
To:jenny@compail.ca
Subject:School term
Date:01/09 6:00 p.m.
Dear Jenny,
Today is my first day of new high school.Many students in our school come from big cities.They bring the high-tech things to school,for example,mobile phones,MP3 players,CD players and electronic dictionaries.They show off these things to others.What about your classmates in the US? Do they have these things?
Li Hong
From:jenny@compail.ca
To:Li-Hong @ net. cn
Subject:Repeat!
Date:01/09 8:00 p.m.
Dear Li Hong.
We also bring these high-tech things when we are back to school.However,we often work during the holidays,and make money to buy these things.I think we need these things.We need mobile phones to contact with our friends.We also need CD players to listen to music.Electronic dictionaries can be useful for our study too.
Jenny
 
小题1:The word “high-tech” means ____________ in Chinese.
A.高质量的B.高品质的C.高科技的D.高价格的
小题2:Where do you probably read these two letters?
A.In a magazine.B.In a book.C.In a guide-book.D.On a website.
小题3: Li Hong thinks many students like to bring the high-tech things to school because ____________.
A.they like to listen to music
B.mobile phones are useful for their studies
C.they want to show off these things
D.they want to contact with their classmates
小题4:Jenny thinks students bring CD players to school because they want to _________.
A.make money B.contact with friends C.listen to musicD.study well
小题5:From the passage we know that ____________.
A.Li Hong has many high-tech things like her classmates
B.American students often use their own money to buy the high-tech things
C.Chinese students work during the holidays to buy the high-tech things
D.all the high-tech things are useful for the students
单项选择题