Name: ______________________________ Class No.: _______________ Quiz: Thermodynamics Time allowed: 15 minutes Molar gas constant R= 8.31 J/mole, molecular mass of O2 and H2 are 32 gm/mole and 2 gm/mole. 1. P I (P1, V1, T1) II (P1, V2, T3) a. If T1 = T2 = 27oC, V1= 2 lit, V2=4 lit, how much work is done by the 64 gm of oxygen at 27oC (constant) Working gas is O2 when it expands from 2 lit to 4 lit., i.e. I III directly? b. How much work is done by the 64 gm of oxygen if I II III? III (P2, V2, T2) V1 2. V2 V H2 gas is stored in a 10 lit container at 50 atm pressure, 27oC. Some H2 is used and the pressure decreases to 10 atm pressure, 17oC. How much gas is used? Name: ______________________________ Class No.: _______________ Quiz: Thermodynamics Time allowed: 15 minutes Molar gas constant R= 8.31 J/mole, molecular mass of O2 and H2 are 32 gm/mole and 2 gm/mole. 1. P I (P1, V1, T1) II (P1, V2, T3) c. If T1 = T2 = 27oC, V1= 2 lit, V2=4 lit, how much work is done by the 64 gm of oxygen at 27oC (constant) Working gas is O2 when it expands from 2 lit to 4 lit., i.e. I III directly? d. How much work is done by the 64 III (P2, V2, T2) V1 3. V2 gm of oxygen if I II III? V H2 gas is stored in a 10 lit container at 50 atm pressure, 27oC. Some H2 is used and the pressure decreases to 10 atm pressure, 17oC. How much gas is used? Answers 1. a. W M RT ln V2 64 4 8.31 300 ln 3480 J V1 32 2 M b. W I , II , III 0 p1 (V2 V1 ) 2. RT V1 (V2 V1 ) 64 8.31 300 2 10 3 4990 J 3 32 2 10 pV nRT n pV pV M pV pV M 1 1 2 2 RT RT R T1 T2 3.12 10 2 kg