双语物理化学各章习题 下载本文

this process.

答案:Q=27.24kJ, W=-6.81kJ, △U=20.429kJ, △H=34.048kJ

9. 已知水(H2O,l)在100℃的饱和蒸气压p*?101.325kPa,在此温度、压力下水的摩尔蒸发焓?vapHm?40.668kJ?mol?1。求在100℃,101.325kPa下使1kg水蒸气全部凝结成液体水时的Q,W,△U和△H。设水蒸气适用理想气体状态方程。 Calculate the Q,W, △U,△H of the following process: 1kg H2O(g, 100℃,101.325kPa)→H2O(l, 100℃,101.325kPa). Given that: p*(H2O,100℃)=101.325kPa, △vapHm(H2O,100℃)= 40.668kJ·mol-1, Supposing the vapor obeys the state equation of perfect gas 答案:Q=△H=-2257kJ, W=172.2kJ, △U=-2085kJ 10. (1)1mol水在100℃,101.325kPa恒压蒸发为同温同压下的蒸气(假设为理想气体)吸热为40.67kJ/mol,求:上述过程的Q,W,△U和△H?(2)始态同上,当外压恒为50kPa时将水恒温蒸发,然后将此1mol, 100℃,50kPa的水蒸气恒温可逆加压变为末态100℃,101.325kPa的水蒸气,求此过程的Q,W,△U和△H?(3)将1mol水(100℃,101.325kPa)在真空中蒸发为同温同压的水蒸气,求过程的Q,W,△U和△H? (1) 1mol water under 100℃ and 101.325kPa is vaporized at an external constant pressure to vapor with the same temperature and same pressure( Assume as perfect gas), the heat absorbed in this process is 40.67kJ/mol. Calculate the Q,W, △U,△H of process.

(2)The initial state is same as (1), firstly the water is isothermal vaporized at an external constant pressure of 50kPa, then the vapor is isothermal reversible compressed from 100℃,50kPa to the 100℃,101.325kPa . Calculate the Q,W, △U,△H of the process (3)1mol water under 100℃and 101.325kPa is vaporized isothermally to vacuum and is changed to vapor with the same temperature and same pressure. Calculate the Q,W, △U,△H of process.

答案:(1)Q=△H=40.67kJ, W=-3.102kJ, △U=37.57kJ;(2) Q=38.48kJ;△H=40.67kJ, W=-0.911kJ, △U=37.57kJ;(3) Q=△U =37.57kJ, W=0kJ, △H =40.67kJ 11. 2mol,60℃,100kPa的液态苯在恒外压下全部变为60℃,24kPa的蒸气,请计算该过程的Q,W,△U和△H?(已知40℃时,苯的蒸气压为24kPa,汽化焓为33.43kJ/mol,假定苯(l)和(g)的摩尔定压热容可近似看做与温度无关,分别为141.5J?mol?K94.12J?mol?K,忽略液体的体积)

2mol liquid benzene under 60℃and 100kPa is vaporized completely at an external constant pressure to vapor of 60℃and 24kPa. Calculate the Q,W, △U,△H of process.

?1?1?1?1及

(Given p*(C6H6,40℃)=24kPa, △vapHm(C6H6,40℃)= 33.43kJ·mol-1,

Cp,m?C6H6,l??141.5J?mol?1?K?1, Cp,m?C6H6,g??94.12J?mol?1?K?1,

bothCp,m?C6H6,l? and Cp,m?C6H6,g? don’t change with temperature, the volume of liquid can be omitted).

答案:Q=△H=64.96kJ, W=-5.54kJ, △U=59.42kJ

12. 已知C(石墨)及H2(g)在25℃时的标准摩尔燃烧焓分别为?393.51kJ?mol?1及

?285.84kJ?mol?1;水在25℃时的汽化焓为44.0kJ?mol?1,反应:C(石墨)+

2H2O(g)→2H2 (g)+ CO2 (g)在25℃时的标准摩尔反应焓?rHm?298.15K?为多少?

???Given at 25℃ , ?cHm (C, graphite)= -393.51kJ/mol, ?cHm (H2, g)= -285.84kJ/mol;

△vapHm(H2O,25℃)= 40.0kJ·mol-1, Calculate ?rHm?298.15K?of the following reaction

?at 25℃.: C(graphite)+2H2O(g)→2H2 (g)+ CO2 (g) 答案:?rHm?298.15K?=90.17kJ?mol

??113. 气相反应A(g) +B(g)→Y(g)在500℃,100kPa进行。已知数据: 物质 A(g) B(g) Y(g) ???fHm?298.15K?/kJ?mol?1 25℃~500℃的Cp,m/J?mol?K 19.1 4.2 30.0 ??1?1-235 52 -241 ?试求?rHm?298.15K?、?rHm?773.15K?、?rUm?773.15K?

?For gas reaction A(g) +B(g)→Y(g) proceeds at 500℃,100kPa. The date is shown in the

following table: substance A(g) B(g) Y(g) ???fHm?298.15K?/kJ?mol?1 25℃~500℃的Cp,m/J?mol?K 19.1 4.2 30.0 ??1?1-235 52 -241 ?Calculate ?rHm?298.15K?、?rHm?773.15K?、?rUm?773.15K? of the reaction.

?答案:?58kJ?mol,?54.82kJ?mol,?48.39kJ?mol

14. 25℃下,密闭恒容的容器中有10g固体萘C10H8(s)在过量的O2(g)中完全燃烧成CO2 (g)和H2O(l)。过程放热401.727kJ。求:

(1) C10H8(s)+12O2(g)=10CO2 (g)+4H2O(l)的反应进度;

?? (2) C10H8(s)的?cUm;(3) C10H8(s)的?cHm

?1?1?1Under 25℃ and in a tightly closed isochoric container, 10g C10H8(s) was completely combusted into CO2 (g) and H2O(l) in excess O2(g) , releasing heat of 401.727kJ in this process. Please calculate:

(1)Extent of reaction :C10H8(s)+12O2(g)=10CO2 (g)+4H2O(l);

?? (2) ?cUm of C10H8(s); (3) ?cHm of C10H8(s).

答案:78.019mmol;-5149.1kJ/mol;-5154.1kJ/mol

第三章 热力学第二定律

一、选择题

1.由热力学第二定律可知,在任一循环过程中( )。 (A)功和热可以完全互相转换;(B)功可以完全转换为热,而热却不能完全转换为功;(C)功和热都不能完全互相转换;(D)功不能完全转换为热,而热却可以完全转换为功;

2.在封闭系统内发生任何绝热过程的△S( ) (A)一定大于零;(B)一定小于零;(C)等于零;(D)可能大于零也可能等于零 3.在隔离系统内发生任何明显进行的过程,则此过程的总熵变△(A)>0;(B)=0;(C)<0;(D)条件不全无法确定

4.在绝热、恒压、W’=0的封闭系统内,发生下列化学过程:

C2H5OH(l) + 3O2(g) = 2CO2(g) + 3H2O(g),此过程的W( );△rHm( );△rUm( );△rSm( ). (A)>0;(B)=0;(C)<0;(D)条件不全无法确定

5.在绝热、恒容、W’=0的封闭系统内,发生下列化学过程:

CH3OH(g) + 1.5O2(g) = CO2(g) + 2H2O(g),此过程的W( );△rHm( );△rUm( );△rSm( ). (A)>0;(B)=0;(C)<0;(D)无法确定

6.物质的量一定的双原子理想气体,经节流膨胀后,系统的压力明显下降,体积变大,此过程的W( );Q( );△U( );△H( );△S( );△G( );△A( )。 (A)>0;(B)=0;(C)<0;(D)无法确定

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S=( )

7.物质的量一定的某实际气体,向真空中绝热膨胀之后,系统的p和V之积变小,此过程W( );Q( );△U( );△H( );△S( ); (A)>0;(B)=0;(C)<0;(D)无法确定 8.非理想气体绝热可逆压缩过程的△S( )。 (A)>0;(B)=0;(C)<0;(D)无法确定 9.碘I2(s)在指定温度的饱和蒸气压下升华为碘蒸气I2(g),此过程的W( );Q( );△U( );△H( );△S( );△G( );△A( )。 (A)>0;(B)=0;(C)<0;(D)无法确定

10.在0℃、101.325kPa的外压下,H2O(s)=H2O(l),此过程的W( );Q( );△U( ); △H( );△S( );△G( );△A( )。 (A)>0;(B)=0;(C)<0;(D)无法确定

11.同一温度、压力下,一定量某纯物质的熵值( )。

(A) S(g)>S(l)>S(s) (B) S(g)

(A)>0;(B)=0;(C)<0;(D)无法确定

13.一定条件下,一定量的纯铁与碳钢相比,其熵值是( )。

(A) S(纯铁)>S(碳钢) (B) S(纯铁)

??p?T(A)>0;(B)=0;(C)<0;(D)无法确定 15.下列哪一个关系式是不正确的?( )

(A) ???G???V (B) ??p?T??G?????S ??T?p???A/T?????G/T??UH????(C) ? (D) ???2?TT?TT??V??p16.物质的量为n的理想气体恒温压缩,当压力由p1变到p2时,其△G是( )。 (A) nRTln??p1?? (B) ?p2??p2p1?p?npdp (C) V?p2?p1? (D) nRTln?2?

?p?RT?1?