CORRECTION
CORRECTION
I n the article “Thermodynamic Functions of 1,2-transDifluorodiazine” by Emile Rutner [J. CHEM. ENG. DATA 7, 398 (1962)], the following correction should be noted. The column headings S o / R and - ( F o - E : ) / R T should be transposed. The values for - ( F o - E:) / RT which have been corrected are given below:
I n the article “Heats of Combustion of trans-Stilbene and tran~-2,2’,4,4’,6,6’-Hexanitrostilbene (HNS)” by Sidney Marantz and George T. Armstrong [J. CHEM.ENG. DATA 13, 118 (1968)], by mistake the heats of formation derived for the two compounds were given with reversed signs. When properly calculated from the experimental heats of combustion and auxiliary data given, AH? [trans-Stilbene (c)] is +32.68 kcal. mole-’ and AH? [HNS(c)] is +13.88 kcal. mole-’. The heats of formation of the corresponding gases become +53.36 and +56.98 kcal. mole-’, respectively. For the calculation of the effect on E ( C = C ) of the substitution of six nitro groups on stilbene, Domalski suggests ( 2 ) , on the basis of a review of the data on T N T which he has made as part of a comprehensive review of the combustion calorimetry of organic compounds, that a careful recalculation of the data of Badoche ( I ) leads to AH? [TNT(g)] = +12.92 kcal. mole-’, rather than +15.5 kcal. mole-’ which the authors used. The combustion data of Badoche lead to *p[TNT(c)] = -15.38 kcal. mole ’, and the sublimation data of Edwards ( 3 ) lead t o AHs [ T N T ( c ) ] = +28.3 kcal. mole-’, from which the above value is obtained. When applied to the calculation of the bond energy changes as in the Marantz and Armstrong article, these values lead to A E ( C = C ) = -1.7 kcal. mole ’ for the effect of six nitro groups substituted on trans-stilbene. Thus the weakening effect is much less pronounced than had been previously concluded. A substantial uncertainty is attached to this value owing to differences in auxiliary data available. For instance from their own vapor pressure data, Nitta et al. ( 4 ) calculated aH,[ T N T ( c ) ] = +24.43 kcal. mole-’, which differs from Edwards by 3.87 kcal. mole-’. If this were taken as the vaporization energy of T N T ( c ) , then A E ( C = C ) would be -9.44 kcal. mole-’. The authors wish to thank S.Benson for calling attention to the error mentioned above and t o E . S. Domalski for the new information given.
Table I. (Corrected)
P K.
-(P - EOo)/RT“
100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 2600 2700 2800 2900 3000
21.79 24.61 26.38 27.77 28.96 30.01 30.95 31.81 32.61 33.34 34.03 34.67 35.27 35.84 36.38 36.89 37.38 37.85 38.29 38.72 39.13 39.52 39.90 40.26 40.61 40.95 41.28 41.60 41.91 42.21
T” K. 3100 3200 3300 3400 3500 3600 3700 3800 3900 4000 4100 4200 4300 4400 4500 4600 4700 4800 4900 5000 5100 5200 5300 5400 5500 5600 5700 5800 5900 6000
-.(FO - EOo)/RT” 42.50 42.78 43.05 43.32 43.58 43.84 44.08 44.33 44.56 44.79 45.02 45.24 45.45 45.66 45.87 46.07 46.27 46.47 46.66 46.84 47.03 47.21 47.39 47.56 47.73 47.90 48.07 48.23 48.39 48.55
Dimensionless.
-
CORRECTION
LITERATURE CITED
I n the article “Halogenated Phthalimidoacetic Acids” by L. M. Caswell and E . D. Martinez [J.CHEM.ENG.DATA13, 286-7 (196811, the last sentence of the text should read: Table I1 summarizes data for the bonds corresponding to the phthalimidoacetic acid bonds a t 292.5 nanometers (log emax 3.38) in 95% ethanol and a t 269 nanometers (log emax 3.04) in dilute sodium hydroxide ( 3 ) .
(1) Badoche, M., Bull. SOC.Chim. 6, 570 (1939). (2) Domalski, E. S., National Bureau of Standards, Washington, D. C., private communication, 1968. (3) Edwards, G., Trans. Faraday SOC.46, 423 (1950). (4) Nitta, I., Seki, S., Momotani, M., Sato, K., Nippon Kugaku Zasshi 71, 378-82 (1950).
VOL. 13, No. 3, JULY 1968
455
