TG, DTA Pyrolytic Analysis of Cobalt, Nickel, Copper, Zinc, and 5,8-Dihydroxy-1,4-Naphthoquinone Chelate Complexes

Table 1

Analytical data on nonisothermal decomposition of [(C₁₀H₆O₄)₃ (Zn)₂] 2½ H₂O.

Reaction	Loss	Composition	Found	Calc.
Plateau I, ambient at 24.1°C	—	(C10H6O4)3 (Zn)2 2½ H2O	—	—
Sigmoid I	2½H2O
24.1°C–100°C
Ti °C			24.1	—
Tf °C			100	—
Loss to
(C10H6O4)3 (Zn)2			6.30	6.37
Plateau II, 100°–150°C		(C10H6O4)3 (Zn)2
Sigmoid II	½C10H6O4
150°–200°C
Ti °C			150
Tf °C			200
Loss to
5/2 (C10H6O4) (Zn)2			17.80	18.12
Plateau III, 200°–500°C		5/2 (C10H6O4) (Zn)2
Sigmoid III
500°–529°C
Ti °C			500
Tf °C			529
Loss to
(C10H6O4)2 (Zn)2	½C10H6O4		29.90	31.54
Plateau IV, 529°–600°C		(C10H6O4)2 (Zn)2
Sigmoid IV	^C10^H6^O4
600°–700°C
Ti °C			600
Tf °C			700
Loss to
(C10H6O4) (Zn)2			55.76	57.05
700^o onwards