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1.13(b) Calculate the pressure exerted by 1.0 mol H2S behaving as (a) a perfect gas, (b) a van der Waals gas when it is confined under the following conditions: (i) at 273.15 K in 22.414 dm3, (ii) at 500 K in 150 cm3. Use the data in Table 1.6. 1.28 Balloons are still used to deploy sensors that monitor meteorological phenomena and the chemistry of the atmosphere. It is possible to investigate some of the technicalities of ballooning by using the perfect gas law. Suppose your balloon has a radius of 3.0 m and that it is spherical. (a) What amount of H2 (in moles) is needed to inflate it to 1.0 atm in an ambient temperature of 25°C at sea level? (b) What mass can the balloon lift at sea level, where the density of air is 1.22 kg m−3? (c) What would be the payload if He were used instead of H2? 2.8 For an ideal gas, express the deriv<:\tive (8p/8 T)v in terms of ex and K. 3.16 At high pressures (small volumes), the van der Waals equation, Eq. (3 . 1 3), can be rearranged to the form v = b + ; (b + R p T)V2 _ (;)V3. If the quadratic and cubic terms are dropped, then we obtain Vo = b as a first approximation to the smallest root of the equation. This would represent the volume of the liquid. Using this approximate value of V in the higher terms, show that the next approximation for the volume

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1.13(b) Calculate the pressure exerted by 1.0 mol H2S behaving as (a) aperfect gas, (b) a van der Waals gas when it is confined under the followingconditions: (i) at 273.15 K in 22.414 dm3, (ii) at 500 K in 150 cm3. Use the data in Table 1.6.

1.28 Balloons are still used to deploy sensors that monitor meteorologicalphenomena and the chemistry of the atmosphere. It is possible to investigatesome of the technicalities of ballooning by using the perfect gas law. Supposeyour balloon has a radius of 3.0 m and that it is spherical. (a) What amount ofH2 (in moles) is needed to inflate it to 1.0 atm in an ambient temperature of25°C at sea level? (b) What mass can the balloon lift at sea level, where thedensity of air is 1.22 kg m−3? (c) What would be the payload if He were usedinstead of H2?

2.8 For an ideal gas, express the deriv<:\tive (8p/8 T)v in terms of ex and K.

3.16 At high pressures (small volumes), the van der Waals equation, Eq. (3 . 1 3), can be rearrangedto the formv = b + ; (b +RpT)V2 _ (;)V3.If the quadratic and cubic terms are dropped, then we obtain Vo = b as a first approximationto the smallest root of the equation. This would represent the volume of the liquid. Using thisapproximate value of V in the higher terms, show that the next approximation for the volumeof the liquid is V = b + b2R Tja. From this expression show that the first approximation for thecoefficient of thermal expansion of a van der Waals liquid is ex = bRja.

1.13 ( b ) Hitunglah tekanan yang diberikan oleh 1,0 mol H2S berperilaku seperti ( a)gas sempurna , ( b) van der Waals gas bila terbatas di bawah berikutkondisi : ( i ) pada 273,15 K 22,414 dm3 , ( ii ) di 500 K di 150 cm3 . Menggunakan data dalam Tabel 1.6 .

1.28 Balon masih digunakan untuk menyebarkan sensor yang memantau meteorologifenomena dan kimia atmosfer . Hal ini dimungkinkan untuk menyelidikibeberapa teknis dari balon dengan menggunakan hukum gas sempurna. mengirabalon Anda memiliki radius 3,0 m dan bahwa itu adalah bola . ( a) Berapakah jumlahH2 ( dalam mol ) diperlukan untuk mengembang ke 1,0 atm pada suhu ambien25 ° C pada permukaan laut ? ( b ) Berapa massa dapat mengangkat balon di permukaan laut , di manakepadatan udara 1,22 kg m- 3 ? ( c ) Apa yang akan menjadi payload jika Dia digunakanbukannya H2 ?

2.8 Untuk gas ideal , mengungkapkan deriv < : \ tive ( 8p / 8 T ) v dalam hal ex dan K.

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3.16 Pada tekanan tinggi ( volume kecil), der Waals persamaan van , Persamaan. ( 3 . 1 3 ) , dapat diatur kembalike formulirv = b + (b +RpT ) V2 _ ( ;) V3 .Jika istilah kuadrat dan kubik yang jatuh , maka kita memperoleh Vo = b sebagai pendekatan pertamake akar terkecil dari persamaan. Hal ini akan mewakili volume cairan . menggunakanNilai perkiraan V dalam istilah yang lebih tinggi , menunjukkan bahwa pendekatan berikutnya untuk volumecairan adalah V = b + B2R Tja . Dari ungkapan ini menunjukkan bahwa pendekatan pertama untukkoefisien ekspansi termal dari van der Waals cair ex = bRja .