高压下氧气在水中溶解度计算饱和蒸汽压

1、在25Mpa压力下，液体中的溶解氧是多少？就是水，里面加了一些杀菌剂和防腐剂，不过时间长了，可能已经被氧化掉了你可以按照水的溶解度计算补充回答：氧在水中的溶解度和溶解氧值是两个既相区别而又相联系的概念。氧在水中的溶解度指的是水体和大气处于平衡时氧的最大溶解浓度，它的数值与温度、压力、水中溶质量等因素有关。水中溶解氧值则一般是指非平衡状态下的水中溶解氧的浓度。它的数值与水体曝气作用、光合作用、呼吸作用及水中有机污染物的氧化作用等因素有关。这两个概念之间的差异是由于大气和水体界面间氧气传质动力过程较慢而引起的。S在水中的溶解度若已知当25 C下水蒸气在空气中含量为 0.0313摩尔分数以及干空气中

2、含 20.95 % O2时，则可应用道尔顿分压定律和亨利定律算出标准条件下氧在水中溶解度O2(aq):O2(aq) : =Ko2 po2=1.28 X10-8 X (1.0000-0.0313 ) 0X1.013 刈05 XO.2095=2.63 X10-4mol/L (相当于 8.4mg/L )由(4-2)式可导出在定压条件下温度对氧气在水中溶解度影响的关系式：1 C2 AH 11 '5 C 2 303R T Ta 式中C1和C2 分别为绝对温度 T1和T2下气体在水中溶解度(mg/L );H溶解热(J/mol );R气体常数(8.314J/K mol)。压力对氧气在水中溶解度的影响

3、可用下列公式表述：£11.013X105 -pi *式中C1和C2 分别为标准气压和 P2气压下氧气在水中的溶解度( mg/L );p确定温度下饱和水蒸气的压力(p和P2的单位为帕)。P:25C水饱和蒸汽压为3.169 103PaC1: =2.63 X10-4mol/L (相当于 8.4mg/L ) N2 : 8.93 10-4mol/LC2：现在增压罐压力 0.8MPa,即8.0 >105Pa,计算得：C2=21.356刈0-4moL/L=0.1367g/L=0.0478L/L，约 100L 水溶解 4.78L 氧气计算得：C2=72.51 刈0-4moL/L=0.203g/

4、L=0.1624L/L,约 100L水溶解 16.24L氮气饱和蒸气压饱和蒸气压(saturated vapor pressure )在密闭条件中，在一定温度下,与液体或固体处于相 平衡的蒸气所具有的压力称为饱和蒸气压。同一 物质在不同温度下有不同的蒸气压，并随着温度的升高而增大。不同液体饱和蒸汽压不同，溶质的饱和蒸汽压大于溶液的饱和蒸汽压；对于同一物质，固态的饱和蒸汽压大于液态的饱和蒸汽压。例如，在 30 C时，水的饱和蒸气压为4132.982Pa, 乙醇 为10532.438Pa 。而在100 C时，水的饱和蒸气压增大到101324.72Pa,乙醇为222647.74Pa 。饱和蒸气压是液

5、体的一项重要物理性质如液体的沸点、液体混合物_的相对挥发度等都与之有关。饱和蒸气压曲线水在不同温度卜的饱和烝气压SaturatedWater VaporPressures atDifferent Temperatures饱和蒸气压饱和蒸气压饱和蒸气压温度(Saturated温度(Saturated温度(Saturated(Temperatur(Temperatur(Temperature)water vapore)water vapore)water vaporpressure)pressure)pressure)t/C/( X10A3 Pa)t/C/(x 10A3Pa)t/C/( x&quo

6、t;3 Pa)00.61129125232.012503973.610.65716126239.242514041.220.70605127246.662524109.630.75813128254.252534178.940.81359129262.042544249.150.87260130270.022554320.260.93537131278.202564392.271.0021132286.572574465.181.0730133295.152584539.091.1482134303.932594613.7101.2281135312.932604689.4111.312913

7、6322.142614766.1121.4027137331.572624843.7131.4979138341.222634922.3141.5988139351.092645001.8151.7056140361.192655082.3161.8185141371.532665163.8171.9380142382.112675246.3182.0644143392.922685329.8192.1978144403.982695414.3202.3388145415.292705499.9212.4877146426.852715586.4222.6447147438.672725674

8、.0232.8104148450.752735762.7242.9850149463.102745852.4253.1690150475.722755943.1263.3629151488.612766035.0273.5670152501.782776127.9283.7818153515.232786221.9294.0078154528.962796317.2304.2455155542.992806413.2314.4953156557.322816510.5324.7578157571.942826608.9335.0335158586.872836708.5345.32291596

9、02.112846809.2355.6267160617.662856911.1365.9453161633.532867014.1376.2795162649.732877118.3386.6298163666.252887223.7396.9969164683.102897330.2407.3814165700.292907438.0417.7840166717.832917547.0428.2054167735.702927657.2438.6463168753.942937768.6449.1075169772.522947881.3459.5898170791.472957995.2

10、4610.094171810.782968110.34710.620172830.472978226.84811.171173850.532988344.54911.745174870.982998463.55012.344175891.803008583.85112.970176913.033018705.45213.623177934.643028828.35314.303178956.663038952.65415.012179979.093049078.25515.7521801001.93059205.15616.5221811025.23069333.45717.324182104

11、8.93079463.15818.1591831073.03089594.25919.0281841097.53099726.76019.9321851122.53109860.56120.8731861147.93119995.86221.8511871173.8312101336322.8681881200.1313102716423.9251891226.1314104106525.0221901254.2315105516626.1631911281.9316106946727.3471921310.1317108386828.5761931338.8318109846929.8521

12、941368.0319111317031.1761951397.6320112797132.5491961427.8321114297233.9721971458.5322115817335.4481981489.7323117347436.9781991521.4324118897538.5632001553.6325120467640.2052011568.4326122047741.9052021619.7327123647843.6652031653.6328125257945.4872041688.0329126888047.3732051722.9330128528149.3242

13、061758.4331130198251.3422071794.5332131878353.4282081831.1333133578455.5852091868.4334135288557.8152101906.2335137018660.1192111944.6336138768762.4992121983.6337140538864.9582132023.2338142328967.4962142063.4339144129070.1172152104.2340145949172.8232162145.7341147789275.6142172187.8342149649378.4942

14、182230.5343151529481.4652192273.8344153429584.5292202317.8345155339687.6882212362.5346157279790.9452222407.8347159229894.3012232453.8348161209997.7592242500.534916320100101.322252547.935016521101104.992262595.935116825102108.772272644.635216932103112.662282694.135317138104116.672292744.235417348105120.792302795.135517561106125.032312846.735617775107108109110111112113114115116117118119120121122123124129.392322899.035717992133.882332952.135818211138.502343005.935918432143.242353060.436018655148.122363115.736118881153.132373171.836219110158.292383288.636319340163.5823932