Table 7 Results of values of the two thermodynamic parameters (Δ) and (Δ) obtained for linear regression by Eqs. 33 and 45 and nonlinear regression (Eqs. 4449).

From: Effect of acid proticity on the thermodynamic parameters of charge transfer resistance in corrosion and passivation of nickel based glass alloy

T

T

ΔG°

Linear Regression

Non Linear Regression

Δ

Δ

Δ

Δ

°C

K

kJ  mol−1

kJ  mol−1

J  K−1  mol−1

kJ  mol−1

J  K−1mol−1

HCl

20

293.15

− 70.626

55.649

432.815

80.850

516.72

30

303.15

− 75.822

71.176

484.90

40

313.15

− 80.440

62.120

455.25

47.55a

320.70a

− 83.766c

55.649b

432.815b

60

333.15

− 88.837

45.638

403.65

80

353.15

− 96.685

31.023

361.63

 

R2 = 0.98279d

σ = 0.0277e

σ = 0.0213e

H2SO4

20

293.15

− 70.238

85.959

534.55

108.00

608.02

30

303.15

− 76.294

99.542

580.03

40

313.15

− 81.890

91.620

554.08

47.55a

320.70a

− 86.007c

85.959b

534.55b

60

333.15

− 92.440

77.203

509.21

80

353.15

− 102.34

64.419

472.21

 

R2 = 0.99458d

σ = 0.0120e

σ = 0.0265e

H3PO4

20

293.15

− 69.240

104.941

594.307

119.61

644.21

30

303.15

− 74.907

113.98

623.08

40

313.15

− 81.320

108.71

606.82

47.55a

320.70a

− 86.037c

104.941b

594.307b

60

333.15

− 93.817

99.113

579.11

80

353.15

− 104.37

90.606

552.11

 

R2 = 0.99786d

σ = 0.0057e

σ = 0.0287e

  1. (a): Crossover temperature Tcr (Fig. 11a and b). (b); current thermodynamic parameters Δ(T) and Δ(T) calculated with Eqs. 48 and 49, respectively. (c): Gibbs free energy of activation (Δ) estimated with Eq. 44. (d): from22. (e): Standard deviation σ.