Thermochemistry of uranium compounds V. Standard enthalpies of formation of the monouranates of lithium,potassium, and rubidium

Enthalpies of reaction, ΔH_r, of the monouranates of lithium, potassium, and rubidium with 1 mol dm^?3 HCl have been measured calorimetrically. From these measurements, and auxiliary determinations of the enthalpies of solution in acid of the chlorides of lithium, potassium, and rubidium and of uranyl chloride, the standard enthalpies of formation of the uranates, ΔH_f^o, have been derived. The results obtained are as follows:

     

2.

Thermochemical properties of benzoic acid derivatives XI. Vapour pressures and enthalpies of sublimation and formation of the six dimethylbenzoic acids     

M. Colomina  P. Jimenez  M.V. Roux  C. Turrion 《The Journal of chemical thermodynamics》1984,16(12):1121-1127

The energies of combustion of 3,4- and 3,5-dimethylbenzoic acids have been revised by combustion calorimetry. Vapour pressures of very pure samples of the six dimethylbenzoic acids have been determined over a range of temperatures near 298 K by the Knudsen-effusion technique. From the experimental results and our previously published thermochemical quantities the following results for the six C₆H₃(CH₃)₂CO₂H isomers at 298.15 K have been derived.

	$\text{ΔH}{}_{\mathrm{r}}\text{/kcal}{}_{\mathrm{th}}\text{mol}{}^{\mathrm{?1}}$	$\text{ΔH}{}_{\mathrm{f}}{}^{\mathrm{o}}\text{(c, 298.15 K)/kcal}{}_{\mathrm{th}}\text{mol}{}^{\mathrm{?1}}$
α-Li2UO4	?(41.77±0.02)	?(463.31±0.84)
K2UO4	?(42.07±0.05)	?(451.39±0.83)
Rb2UO4	?(41.30±0.05)	?(452.00±0.85)

     

3.

Enthalpies of combustion of 1,2-dihydroxybenzene and of six alkylsubstituted 1,2-dihydroxybenzenes     

Maria D.M.C. Ribeiro Da Silva  Manuel A.V. Ribeiro Da Silva  Geoffrey Pilcher 《The Journal of chemical thermodynamics》1984,16(12):1149-1155

The standard (p^o = 101.325 kPa) molar enthalpies of combustion in oxygen at 298.15 K were measured by static-bomb calorimetry and the standard molar enthalpies of sublimation at 298.15 K were measured by microcalorimetry for 1,2-dihydroxybenzene (catechol) and six alkylsubstituted catechols:

Isomer		$\text{Δ}{}_{\mathrm{<mtext>f</mtext>}}\text{H}{}_{\mathrm{m}}{}^{\mathrm{o}}\text{(cr)}$	$\text{Δ}{}_{\mathrm{<mtext>sub</mtext>}}\text{H}{}_{\mathrm{m}}{}^{\mathrm{o}}$	$\text{Δ}{}_{\mathrm{<mtext>f</mtext>}}\text{H}{}_{\mathrm{m}}{}^{\mathrm{o}}\text{(g)}$
	kJ·mol?1	kJ·mol?1	kJ·mol?1
2,6-	?440.7 ± 1.7	99.1 ± 0.2	?341.6 ± 1.7
2,3-	?450.4 ± 1.7	104.6 ± 0.4	?345.8 ± 1.7
2,5-	?456.1 ± 1.6	105.0 ± 0.6	?351.1 ± 1.7
2,4-	?458.5 ± 1.7	103.5 ± 0.3	?355.0 ± 1.7
3,4-	?468.8 ± 1.9	106.4 ± 0.3	?362.4 ± 1.9
3,5-	?466.8 ± 1.7	102.3 ± 0.3	?364.5 ± 1.7

     

4.

Non-bonded sulphur-sulphur interactions in 3,5-dithiaheptane and 3,6-dithiaoctane     

Margret Månsson 《The Journal of chemical thermodynamics》1974,6(12):1153-1159

Enthalpies of combustion and vaporization at 298.15 K have been measured for 3,5-dithiaheptane and 3,6-dithiaoctane. Enthalpies of formation at 298.15 K have been derived for the compounds in the liquid and gaseous states. The results are:

	$\text{?Δ}{}_{\mathrm{<mtext>c</mtext>}}\text{H}{}_{\mathrm{m}}{}^{\mathrm{o}}\text{(cr)/(kJ·mol}{}^{\mathrm{?1}}\text{)}$	$\text{Δ}{}_{\mathrm{<mtext>sub</mtext>}}\text{H}{}_{\mathrm{m}}{}^{\mathrm{o}}\text{/(kJ·mol}{}^{\mathrm{?1}}\text{)}$
Catechol	2864.5 ± 0.8	86.6 ± 1.6
3-Methylcatechol	3505.4 ± 0.5	93.2 ± 1.0
4-Methylcatechol	3504.6 ± 0.6	94.9 ± 1.0
3-isoPropylcatechol	4808.8 ± 1.1	97.8 ± 1.7
4-terButylcatechol	5461.9 ± 0.9	99.3 ± 1.4
3-Methyl-6-isopropylcatechol	5460.2 ± 0.9	96.6 ± 0.9
3,5-diterButylcatechol	8082.7 ± 1.8	100.1 ± 0.6

     

5.

Thermochemical properties of benzoic acid derivatives VIII. Enthalpies of combustion and formation of o-, m-, and p- t-butylbenzoic acids     

M. Colomina  P. Jiménez  R. Pérez-Ossorio  C. Turrión 《The Journal of chemical thermodynamics》1979,11(12):1179-1184

The enthalpies of formation in the crystalline state at 298.15 K of o-, m-, and p-t-butyl-benzoic acids have been determined by static-bomb calorimetry. Vapour-pressure determinations were made by the Knudsen-effusion technique and the sublimation enthalpies at the mean temperatures of the measurement ranges have been derived for the three acids. The values obtained are:

	$\text{ΔH}{}_{\mathrm{f}}{}^{\mathrm{o}}\text{(l)/kJ mol}{}^{\mathrm{?1}}$	$\text{ΔH}{}_{\mathrm{f}}{}^{\mathrm{o}}\text{(g)/kJ mol}{}^{\mathrm{?1}}$
3,5-Dithiaheptane	?116.0 ± 1.5	?65.2 ± 1.5
3,6-Dithiaoctane	?142.5 ± 1.5	?83.0 ± 1.5

     

6.

Thermochemical properties of benzoic acid derivatives X. Enthalpies of combustion and formation of 2,3-, 2,4-, 2,6-, 3,4-, and 3,5-dimethoxybenzoic acids     

M. Colomina  M.V. Roux  C. Turrion 《The Journal of chemical thermodynamics》1981,13(12):1169-1173

The energies of combustion of 2,3-, 2,4-, 2,6-, 3,4-, and 3,5-dimethoxybenzoic acids have been determined by static-bomb calorimetry. The enthalpies of formation in the crystalline state at 298.15 K have been derived for these five acids. The values obtained are:

	$\text{ΔH}{}_{\mathrm{f}}{}^{\mathrm{o}}\text{(c, 298.15 K)/kJ mol}{}^{\mathrm{?1}}$	$\text{ΔH}{}_{\mathrm{s}}\text{/kJ mol}{}^{\mathrm{?1}}$
o-t-butylbenzoic acid	476.2 ± 1.9	99.8 ± 0.4	(at 314.6 K)
m-t-butylbenzoic acid	504.3 ± 1.6	103.0 ± 0.5	(at 326.5 K)
p-t-butylbenzoic acid	502.9 ± 1.7	103.8 ± 0.4	(at 334.1 K)

     

7.

Heat capacity and thermodynamic functions of CsCrCl₃ and RbCrCl₃. Structural phase transitions     

Joaquín García  Juan Bartolomé  Domingo González  Rafael Navarro  Willem Jacobus Crama 《The Journal of chemical thermodynamics》1983,15(12):1109-1126

We present the heat capacities measured by adiabatic calorimetry from 6 to 350 K, and by differential scanning calorimetry from 300 to 500 K, of CsCrCl₃ and RbCrCl₃. A first-order transition at T_c = (171.1±0.1) K was detected for CsCrCl₃. The RbCrCl₃ showed at T_c = (193.3±0.1) K a transition with thermal hysteresis at temperatures just below the maximum. At T₁ = (440±10) K a continuous transition was also detected. Furthermore, at T_N ≈ 16 K, and for both compounds, a small bump due to magnetic long-range ordering was observed. The thermodynamic functions at 298.15 K are

	$\text{?ΔH}{}_{\mathrm{f}}{}^{\mathrm{o}}\text{(c)/kJ mol}{}^{\mathrm{?1}}$
2,3-dimethoxybenzoic acid	687.0 ± 1.4
2,4-dimethoxybenzoic acid	712.2 ± 1.4
2,6-dimethoxybenzoic acid	693.8 ± 1.4
3,4-dimethoxybenzoic acid	714.0 ± 1.4
3,5-dimethoxybenzoic acid	724.0 ± 1.5

     

8.

Thermochemical studies of three bis(O-alkyl-N-benzoylthiocarbamato)nickel(II) complexes     

《The Journal of chemical thermodynamics》2004,36(8):627-631

     

9.

Standard molar enthalpies of formation of two crystalline bis[N-(diethylaminothiocarbonyl)benzamidinato]nickel(II) complexes     

《The Journal of chemical thermodynamics》2004,36(9):753-757

     

10.

Standard molar enthalpies of formation,vapour pressures,and enthalpies of sublimation of 2-chloro-4-nitroaniline and 2-chloro-5-nitroaniline     

《The Journal of chemical thermodynamics》2003,35(8):1343-1359

     

11.

Spectrophotometric studies of neomycin-copper complex and determination of neomycin sulfate using an auxiliary ligand     

J.K. Agrawal  S.G. Harmalkar  R. Vijayavargiya 《Microchemical Journal》1976,21(2):202-208

Spectrophotometric investigation of the deep blue colored, water-soluble complex of

1. Stability constant and free energy of formation of Cu-NMS complex at 30 ± 1 °C

	$\text{C}{}_{\mathrm{<mtext>p,</mtext><mtext>m</mtext>}}\text{R}$	$\text{S}{}_{\mathrm{m}}{}^{\mathrm{o}}\text{R}$	$\text{{H}{}_{\mathrm{m}}{}^{\mathrm{o}}\text{(T)?H}{}_{\mathrm{m}}{}^{\mathrm{o}}\text{(0)}}\text{R}\text{K}$	$\text{?{G}{}_{\mathrm{m}}{}^{\mathrm{o}}\text{(T)?H}{}_{\mathrm{m}}{}^{\mathrm{o}}\text{(0}}\text{RT}$
CsCrCl3	15.38	26.49	3503.2	14.735
RbCrCl3	15.76	25.99	3556.8	14.384

     

12.

Thermochemical studies of three N-thiocarbamoylbenzamidines     

《The Journal of chemical thermodynamics》2004,36(7):555-559

     

13.

Potentiometric study of silver(I)-thiosemicarbazonates     

M.Argüeso Jiménez  M.D.Luque de Castro  M. Valcárcel 《Microchemical Journal》1980,25(3):301-308

A potentiometric method is described for the determination of thiosemicarbazones involving the formation of a complex with Ag(I). This method is proposed for thiosemicarbazones of the following carbonyl compounds: salicylaldehyde, p-hydroxybenzaldehyde, benzaldehyde, picolinaldehyde, 6-methylpicolinaldehyde and p-dimethylaminebenzaldehyde. Stability constants of the complexes are determined by Ringbom and Harju's method.

FIG. 2. Variation of pAg + logα_{PAT (H)} + log ([Ag?PAT)]/[PAT])

2. Formation Constants of the Silver-Thiosemicarbazonates

Method	$\text{log}\text{K}{}_{\mathrm{s}}$	ΔF (Kcal/mole)
Mukherji and Dey (4)	4.11	?5.70
Subhrana and Raghavrao (6)	4.80	?6.66

     

14.

Standard molar enthalpy of formation of monothiodibenzoylmethane by rotating-bomb calorimetry     

《The Journal of chemical thermodynamics》2004,36(6):447-451

     

15.

Thermodynamics of copper sulfides III. Heat capacities and thermodynamic properties of Cu1.75S,Cu1.80S,and Cu1.85S from 5 to about 700 K     

《The Journal of chemical thermodynamics》1987,19(12):1305-1324

     

16.

Thermal properties of XMF3 cubic perovskites II. Heat capacity of NH4ZnF3 and KZnF3     

《The Journal of chemical thermodynamics》1986,18(12):1135-1146

     

17.

Electrical conduction and diffusion studies in NH₄H₂PO₄ and KH₂PO₄ single crystals     

M. Sharon  Anjan K. Kalia 《Journal of solid state chemistry》1977,21(3):171-183

Electrical conduction (dc) studies are made with pure and cobalt(II)-doped single crystals of NH₄H₂PO₄ and KH₂PO₄. The effect of the dopant concentration on the enthalpy for the migration of protons and the enthalpy for the rotation of the H₂PO₄ group have been studied. It is suggested that proton migration occurs through a synchronous phosphate rotation mechanism. Tritium diffusion studies in KDP and ³²PO₄ diffusion in ADP crystals have been made. The mechanisms for the conduction and diffusion processes are found to be different in nature. The distribution coefficients of Co(II) dopant in ADP (2.92 × 10^?3) and KDP (1.14 × 10^?3) are calculated. The following enthalpy values are obtained.

Thiosemicarbazone	Log $\text{K}{}_{\mathrm{<mtext>f</mtext>}}$
-Benzaldehyde	15.5 ± 0.1
-Picolinaldehyde	14.0 ± 0.
-6-Methylpicolinaldehyde	14.5 ± 0.
-Salicylaldehyde	15.7 ± 0.1
-p-Hydroxybenzaldehyde	15.6 ± 0.
-p-Dimethylaminebenzaldehyde	17.2 ± 0.1

     

18.

Standard enthalpies of formation of uranium compounds I. β-UO₃ and γ-UO₃     

E.H.P. Cordfunke  W. Ouweltjes  G. Prins 《The Journal of chemical thermodynamics》1975,7(12):1137-1142

The standard enthalpy of formation of γ-UO₃ has been critically assessed; the value ?(292.5 ± 0.2) kcal_th mol^?1 is suggested.The enthalpies of solution of β-UO₃ and γ-UO₃ in 3 M H₂SO₄ have been measured and used to derive:

$\text{ΔH}{}_{\mathrm{f}}{}^{\mathrm{°}}\text{(β?}\text{UO}{}_3\text{, 298.15}\text{K}\text{) = ?(291.6 ± 0.2)}\text{kcal}{}_{\mathrm{th}}\text{mol}{}^{\mathrm{?}}$

     

19.

A new kinetic method for the determination of magnesium and its application to natural waters     

M. Ternero  F. Pino  D.Pérez Bendito  M. Valcárcel 《Microchemical Journal》1980,25(1):102-110

A kinetic method is described for the determination of trace amounts of magnesium in the presence of calcium. The procedure is based on the inhibition of the manganese(II) catalyzed aerial oxidation of 1,4-dihydroxyphthalimide dithiosemicarbazone reaction by

2. Effect of Transition Metals^a

	KDP (eV)	ADP (eV)
Enthalpy for the migration of protons	0.01 ± 0.01	0.15 ± 0.02
Enthalpy for the rotation of phosphate group	0.71 ± 0.01	0.66 ± 0.01
Enthalpy for T-diffusion	0.14 ± 0.01	—
Enthalpy for 32PO4 diffusion	—	0.24 ± 0.01

Transition metal	Concentration (M)	Percentage inhibition	Mg(II) found (×l05M)
Fe(II)	3.6.10?5	54.1	4.62
Fe(III)	3.6.10?5	47.8	4.48
Co(II)	3.4.10?5	50.0	4.53
Ni(II)	3.4.10?5	50.0	4.53
Cu(II)	3.1.10?5	52.0	4.56
Zn(II)	3.0.10?5	54.1	4.62
Cd(II)	1.7.10?5	52.0	4.56
Hg(II)	9.9.10?6	45.8	4.44
Sn(II)	2.1.10?6	50.0	4.52
Pb(II)	1.2.10?6	54.1	4.62

a

Conditions: 4.53.10^?5M Mg(II), 35 ng Mn ml^?1, 0.429 M ammonia, 1.6.10^?4M OH-PDT.

3. Determination of Magnesium in Natural Waters

			Mg(II) found (M)b
Natural water	Ca(II) presenta		Atomic absorption
sample	M	Kinetic absorption	method
Commercial	3.45 · 10?4	1.65 · 10?3	1.74 · 10?3
Commercial	5.46 · 10?4	1.57 · 10?4	1.81 · 10?4
Untreated	6.13 · 10?4	2.16 · 10?4	2.40 · 10?4
Treated	4.95 · 10?4	1.93 · 10?4	2.17 · 10?4

a

EDTA titration less the magnesium.

b

Average of three separate determinations. traces of magnesium(II). The reaction is followed spectrophotometrically by measuring the rate of change in absorbance at 594 nm. The calibration graph (percentage inhibition vs magnesium concentration) is linear in the range 329–535 · 10^?5M with an accuracy and precision of 1.2%. The method has been applied to the determination of magnesium in natural waters at low concentrations.

     

Thermochemical properties of benzoic acid derivatives XI. Vapour pressures and enthalpies of sublimation and formation of the six dimethylbenzoic acids

The energies of combustion of 3,4- and 3,5-dimethylbenzoic acids have been revised by combustion calorimetry. Vapour pressures of very pure samples of the six dimethylbenzoic acids have been determined over a range of temperatures near 298 K by the Knudsen-effusion technique. From the experimental results and our previously published thermochemical quantities the following results for the six C₆H₃(CH₃)₂CO₂H isomers at 298.15 K have been derived.

Enthalpies of combustion of 1,2-dihydroxybenzene and of six alkylsubstituted 1,2-dihydroxybenzenes

The standard (p^o = 101.325 kPa) molar enthalpies of combustion in oxygen at 298.15 K were measured by static-bomb calorimetry and the standard molar enthalpies of sublimation at 298.15 K were measured by microcalorimetry for 1,2-dihydroxybenzene (catechol) and six alkylsubstituted catechols:

Non-bonded sulphur-sulphur interactions in 3,5-dithiaheptane and 3,6-dithiaoctane

Enthalpies of combustion and vaporization at 298.15 K have been measured for 3,5-dithiaheptane and 3,6-dithiaoctane. Enthalpies of formation at 298.15 K have been derived for the compounds in the liquid and gaseous states. The results are:

Thermochemical properties of benzoic acid derivatives VIII. Enthalpies of combustion and formation of o-, m-, and p- t-butylbenzoic acids

The enthalpies of formation in the crystalline state at 298.15 K of o-, m-, and p-t-butyl-benzoic acids have been determined by static-bomb calorimetry. Vapour-pressure determinations were made by the Knudsen-effusion technique and the sublimation enthalpies at the mean temperatures of the measurement ranges have been derived for the three acids. The values obtained are:

Thermochemical properties of benzoic acid derivatives X. Enthalpies of combustion and formation of 2,3-, 2,4-, 2,6-, 3,4-, and 3,5-dimethoxybenzoic acids

The energies of combustion of 2,3-, 2,4-, 2,6-, 3,4-, and 3,5-dimethoxybenzoic acids have been determined by static-bomb calorimetry. The enthalpies of formation in the crystalline state at 298.15 K have been derived for these five acids. The values obtained are:

Heat capacity and thermodynamic functions of CsCrCl3 and RbCrCl3. Structural phase transitions

We present the heat capacities measured by adiabatic calorimetry from 6 to 350 K, and by differential scanning calorimetry from 300 to 500 K, of CsCrCl₃ and RbCrCl₃. A first-order transition at T_c = (171.1±0.1) K was detected for CsCrCl₃. The RbCrCl₃ showed at T_c = (193.3±0.1) K a transition with thermal hysteresis at temperatures just below the maximum. At T₁ = (440±10) K a continuous transition was also detected. Furthermore, at T_N ≈ 16 K, and for both compounds, a small bump due to magnetic long-range ordering was observed. The thermodynamic functions at 298.15 K are

Spectrophotometric studies of neomycin-copper complex and determination of neomycin sulfate using an auxiliary ligand

Spectrophotometric investigation of the deep blue colored, water-soluble complex of

1. Stability constant and free energy of formation of Cu-NMS complex at 30 ± 1 °C

Potentiometric study of silver(I)-thiosemicarbazonates

A potentiometric method is described for the determination of thiosemicarbazones involving the formation of a complex with Ag(I). This method is proposed for thiosemicarbazones of the following carbonyl compounds: salicylaldehyde, p-hydroxybenzaldehyde, benzaldehyde, picolinaldehyde, 6-methylpicolinaldehyde and p-dimethylaminebenzaldehyde. Stability constants of the complexes are determined by Ringbom and Harju's method.

FIG. 2. Variation of pAg + logα_{PAT (H)} + log ([Ag?PAT)]/[PAT])

2. Formation Constants of the Silver-Thiosemicarbazonates

Electrical conduction and diffusion studies in NH4H2PO4 and KH2PO4 single crystals

Electrical conduction (dc) studies are made with pure and cobalt(II)-doped single crystals of NH₄H₂PO₄ and KH₂PO₄. The effect of the dopant concentration on the enthalpy for the migration of protons and the enthalpy for the rotation of the H₂PO₄ group have been studied. It is suggested that proton migration occurs through a synchronous phosphate rotation mechanism. Tritium diffusion studies in KDP and ³²PO₄ diffusion in ADP crystals have been made. The mechanisms for the conduction and diffusion processes are found to be different in nature. The distribution coefficients of Co(II) dopant in ADP (2.92 × 10^?3) and KDP (1.14 × 10^?3) are calculated. The following enthalpy values are obtained.

Standard enthalpies of formation of uranium compounds I. β-UO3 and γ-UO3

The standard enthalpy of formation of γ-UO₃ has been critically assessed; the value ?(292.5 ± 0.2) kcal_th mol^?1 is suggested.The enthalpies of solution of β-UO₃ and γ-UO₃ in 3 M H₂SO₄ have been measured and used to derive:

$\text{ΔH}{}_{\mathrm{f}}{}^{\mathrm{°}}\text{(β?}\text{UO}{}_3\text{, 298.15}\text{K}\text{) = ?(291.6 ± 0.2)}\text{kcal}{}_{\mathrm{th}}\text{mol}{}^{\mathrm{?}}$

     

A new kinetic method for the determination of magnesium and its application to natural waters

A kinetic method is described for the determination of trace amounts of magnesium in the presence of calcium. The procedure is based on the inhibition of the manganese(II) catalyzed aerial oxidation of 1,4-dihydroxyphthalimide dithiosemicarbazone reaction by

2. Effect of Transition Metals^a

The vibrational ground state rotational spectroscopic constants and structure of the HCN dimer

Rotational spectra have been assigned for four isotopic species of the linear HCN dimer in the vibrational ground state. The spectroscopic constants are

     

isotope	-B0 (MHz)	DJ (kHz)	xN1 (MHz)	xN2 (MHz)
HC14N-HC14N	1745.80973(50)	2.133(30)	?4.0973(200)	?4.4400(190)
HC14N-HC15N	1700.30190(30)	1.939(40)	?4.1059(10)	-
HC15N-HC14N	1729.92082(20)	2.023(30)	-	?4.4339(6)
HC15N-HC15N	1684.28825(25)	1.900(30)	-	-