红磷P(s)和Cl2(g)发生反应生成PCl3(g)和PCl5(g).反应过程和

题型:填空题

问题:

红磷P(s)和Cl2(g)发生反应生成PCl3(g)和PCl5(g).反应过程和能量关系如图所示(图中的ΔH表示生成1 mol产物的数据).

根据上图回答下列问题:

(1)P和Cl2反应生成PCl3的热化学方程式是 ___________________________________;

(2)PCl5分解成PCl3和Cl2的热化学方程式是 __________________________________;上述分解反应是一个可逆反应.温度T1时,在密闭容器中加入0.80 mol PCl5,反应达平衡时PCl5还剩0.60 mol,其分解率α1等于________;若反应温度由T1升高到T2,平衡时PCl5的分解率为α2,α2________α1(填“大于”、“小于”或“等于”);

(3)工业上制备PCl5通常分两步进行,先将P和Cl2反应生成中间产物PCl3,然后降温,再和Cl2反应生成PCl5.原因是__________________________;

(4)P和Cl2分两步反应生成1 mol PCl5的ΔH3=________,P和Cl2一起反应生成1 mol PCl5的ΔH4________ΔH3(填“大于”、“小于”或“等于”).

(5)PCl5与足量水充分反应,最终生成两种酸,其化学方程式是_____________________.

考点:影响化学平衡的因素单质磷及其化合物热化学方程式盖斯定律化学平衡的有关计算
题型:填空题

阅读理解。

Boxing Day When is it?

  December 26th. Boxing Day takes place on December 26th or the following

Monday if December 26th falls on a Saturday or Sunday. Where did it come

from?

  Boxing Day began in England, in the middle of the nineteenth century.

Where is Boxing Day celebrated?

  Boxing Day is celebrated in Australia, Britain, New Zealand,and Canada.

How is Boxing Day celebrated?

  There seems to be two thoughts on the beginning of Boxing Day and why it

is celebrated. One of them is that centuries ago, on the day after Christmas,

bosses would give boxes full of food and fruit, clothing,or money to their

servants (仆人). The presents were much like the bonuses(奖金) people receive

today. These presents, given in boxes,gave the holiday its name," Boxing Day".

  Today, Boxing Day is spent with family and friends with lots of food and

share of friendship and love. Government buildings and small businesses are

closed but the  malls ( 购物商场) are open and filled with people exchanging

presents or buying cheaper Christmas presents,cards and so on.

1. If December 26th is a Saturday,when Boxing Day will be celebrated?

A. On December 25th.        

B. On December 26th.

C. On December 27th.        

D. On December 28th.

2. How many countries does the passage mention celebrate Boxing Day?

A. Only one.  

B. Two.    

C. Three.  

D. Four.

3. What does the underlined word" them" refer to?

A. The boxes full of things.

B. The countries which celebrate Boxing Day.

C. Two thoughts on the beginning of Boxing Day and why it is celebrated.

D. The presents that bosses gave their servants.

4. People have a day off on Boxing Day except those who work in _____.

A. government buildings      

B. small companies

C. malls                  

D. post offices

题型:填空题

患者男,56岁。无诱因腹痛、腹腔胀气,血性腹水原因待查。腹腔积液检查:RBC(4+),浆液黏蛋白定性实验(+),WBC160×106/L,N65%,L27%。

下列腹水酶学检查哪一项对该病的诊断最有价值()

A.DA

B.LP

C.CEA

D.LDH

E.ST

题型:填空题

女性,28岁,进食不畅感2月余,饮水时颈部偶有气过水声,应考虑( )

A.先天性巨食管症
B.食管憩室
C.贲门失弛缓症
D.食管裂孔疝
E.Barrett食管

题型:填空题

血浆中()下降时,神经肌肉应激性大增,导致手足抽搐。

A、钾

B、钙

C、铁

D、镁

题型:填空题

分水器

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