FIGURE 19-12 Process ADB consists of an isochoric (AD) and an isobaric(DB) process P A A nRT&(a y W=0到 Isobaric B B W=P(V3-Kk 6 =nRi(-乙 O v= Q+w
Q=0,W=0=>△(=O FIGURE 19-13 Free expansion
Molar specific heats Q=nCy AT(Cv=mc,/n) QnC∠T(CmcD/n
•Molar Specific Heats •Q=nCv⊿T (Cv=mcv/n) •Q=nCp⊿T (Cp=mcp/n)
TABLE 19-3 Specific heats of gases at 15.C Specific heats Molar specific heats cl/kg·K) (cal/mol K Cp -C y P Gas C C V P (cal/mol K) Monatomic He 0.751.15 2.98497 1.67 e 0.1480.246 2.98497 167 Diatomic 0.1770.248 4966.95 19 1.40 0.1550218503703 2.00 140 Triatomic CO 0.1530.199 680883 2.03 1.30 H2O(100C03500482 6.208.20 2.00 1.32 Polyatomic CH 0.3430.41210.301235 2.05 1.20