The Specific Heats of Aqueous Sucrose Solutions at 20 and 25° and the Apparent Molal Heat Capacity of Non-electrolytes1

1937 ◽  
Vol 59 (3) ◽  
pp. 447-452 ◽  
Author(s):  
Frank T. Gucker ◽  
Fred D. Ayres
Keyword(s):  
Heat Capacity ◽  
Specific Heats ◽  
Sucrose Solutions ◽  
Apparent Molal Heat Capacity

scholarly journals The thermal capacity of pure iron

1940 ◽  
Vol 174 (956) ◽  
pp. 1-15 ◽  
Keyword(s):  
Heat Capacity ◽  
Specific Heat ◽  
Thermal Capacity ◽  
Total Heat ◽  
Large Temperature ◽  
Specific Heats ◽  
The Past ◽  
Heat Curve ◽  
Different Temperatures ◽  
The Subject

Although the heat capacity of iron at different temperatures has been the subject of a number of investigations in the past, it is only recently that iron of purity greater than 99.9 % has been available. Furthermore, in most previous determinations the property actually measured has been the total heat over a relatively large temperature range. Specific heats deduced from such measurements are liable to appreciable error, since if the total heat curve is smoothed, small fluctuations in the specific heat will be concealed, whereas if the actual observations are retained without smoothing, fluctuations which have no physical existence may appear in the result. Thus, suppose that the total heat is measured from 50 to 145 and from 50 to 155° C, the former being in error by 1 part in 1000 in excess and the latter the same amount in defect, the error in the specific heat over the range 145-155° C will be almost 2%. Evidently a real variation of 1 or 2% would be liable to pass unnoticed if any smoothing is undertaken, and conversely, fluctuations of this order may be introduced spuriously if the observations are used without smoothing. In general, calorimetry from high temperatures cannot be carried out to an accuracy of 1 part in 1000, and in any case, even this accuracy is insufficient at temperatures of the order of 1000° C.

SPECIFIC HEATS AND LATENT HEAT OF FUSION OF ICE

1930 ◽  
Vol 3 (3) ◽  
pp. 205-213 ◽  
Author(s):  
W. H. Barnes ◽  
O. Maass
Keyword(s):  
Heat Capacity ◽  
Latent Heat ◽  
Adiabatic Calorimeter ◽  
Heat Capacities ◽  
Heat Of Fusion ◽  
Final Temperature ◽  
Latent Heat Of Fusion ◽  
Temperature Range ◽  
Specific Heats

Values for the heat capacities of ice and resulting water from initial temperatures of between 0 °C. and − 78.5 °C. to a final temperature of + 25.00 °C. are measured to ± 0.05% or better with an improved adiabatic calorimeter previously described. The specific heats of ice over the temperature range 0° C. to − 80 °C. are found and the latent heat of fusion of ice at 0 °C. is obtained from these heat capacity determinations.

Apparent Molal Volumes and Heat Capacities of some Sulfates and Carbonates in Water at 25 °C

1975 ◽  
Vol 53 (8) ◽  
pp. 1134-1138 ◽  
Author(s):  
Gérald Perron ◽  
Jacques E. Desnoyers ◽  
Frank J. Millero
Keyword(s):  
Heat Capacity ◽  
Ionic Strength ◽  
Ion Pair ◽  
Heat Capacities ◽  
Anomalous Increase ◽  
Low Concentration ◽  
Apparent Molal Volumes ◽  
Specific Heats ◽  
Molal Volumes ◽  
Apparent Molal Heat Capacities

The densities and volumetric specific heats of Na2SO4, K2SO4, MgSO4, Na2CO3, NaHCO3, and NaOH were measured up to an ionic strength of 1 in water at 25 °C with a flow densimeter and a flow microcalorimeter. From these data, the heat capacity for the formation of the ion pair MgSO40was evaluated as 84.9 J K−1 mol−1. There is an anomalous increase in the apparent molal heat capacities of Na2CO3 at low concentration but the apparent molal volumes are normal. This anomaly can be suppressed with NaOH. Attempts to account quantitatively for this behavior by an hydrolysis correction were not successful.

THE HEAT CONTENT OF WATER ADSORBED ON CELLULOSE

1939 ◽  
Vol 17b (1) ◽  
pp. 40-50 ◽  
Author(s):  
J. H. Shipley ◽  
W. Boyd Campbell ◽  
O. Maass
Keyword(s):  
Heat Capacity ◽  
Experimental Technique ◽  
Heat Content ◽  
Bound Water ◽  
Adsorbed Water ◽  
Adiabatic Calorimeter ◽  
Temperature Range ◽  
Specific Heats ◽  
New Type

The heat capacity of water adsorbed on cellulose has been measured by means of a new type of adiabatic calorimeter and a new experimental technique. Measurements have been made with 2, 4, 8, and 12% adsorbed water over the temperature range − 35° to + 25 °C. with considerable accuracy. A mechanism, that of a change in the amount of bound water with the temperature, has been suggested to explain the high values obtained for the apparent specific heats of adsorbed water.

THE HEAT CAPACITY OF AQUEOUS SOLUTIONS OF HYDROFLUORIC ACID

1946 ◽  
Vol 24b (2) ◽  
pp. 51-56 ◽  
Author(s):  
T. Thorvaldson ◽  
E. C. Bailey
Keyword(s):  
Heat Capacity ◽  
Aqueous Solutions ◽  
Specific Heat ◽  
Hydrofluoric Acid ◽  
Temperature Range ◽  
Apparent Molal Heat Capacity

The heat capacity of aqueous solutions of hydrofluoric acid varying in concentration from 0.55 to 48% was determined over the temperature range 18° to 20 °C. The respective values for the specific heat varied between 0.996 and 0.718 cal. per gm. The values obtained are consistent among themselves but differ markedly from those found in the literature. The apparent molal heat capacity of the solute over this range of concentration and temperature was calculated and compared with values obtained from the data of other experimenters.

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