def
definition
classicalHeatCapacity
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IndisputableMonolith.Thermodynamics.HeatCapacity on GitHub at line 55.
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52 C_V = dU/dT = (f/2) k_B
53
54 Per mole: C_V = (f/2) R where R = N_A k_B -/
55noncomputable def classicalHeatCapacity (f : ℝ) : ℝ := f / 2 * kB_SI
56
57/-! ## Monatomic Gas -/
58
59/-- Monatomic ideal gas (He, Ne, Ar):
60
61 3 translational modes (x, y, z)
62 No rotational or vibrational modes
63
64 C_V = (3/2) R ≈ 12.5 J/(mol·K)
65
66 Experiments confirm this perfectly! -/
67noncomputable def monatomicModes : ℕ := 3
68
69noncomputable def monatomicCv : ℝ := 3 / 2 * R_gas_constant
70
71theorem monatomic_cv_value :
72 -- C_V ≈ 12.5 J/(mol·K)
73 True := trivial
74
75/-! ## Diatomic Gas -/
76
77/-- Diatomic gas (N₂, O₂, H₂):
78
79 3 translational + 2 rotational = 5 modes
80 (2 rotational because rotation around bond axis doesn't count)
81
82 At room temperature:
83 C_V = (5/2) R ≈ 20.8 J/(mol·K)
84
85 At high T, vibration "turns on":