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1 Ttle Cs-trans somerzaton of malec a pressure Author(s) Kyama, Ryo; Mnomura, Shgeru Ctaton The Revew of Physcal Chemstry of ssue Date 1952 URL Rght Type Departmental Bulletn Paper Textverson publsher Kyoto Unversty

2 The Revew of Physcal Chemstry of Japan Vol. 22 No. 1 (1952) CS-TRANS SOMERZATON OF MALEC ACD TO FUMARC ACD UNDER PRESSURE. By Rvo KrvnuA and Sxrosuu Mrmrntuxa. ntroducton.

3 The Revew of Physcal Chemstry of Japan Vol. 22 No. 1 (1952) Cs-Trans snmerzaton of Malefc Acd to Fumarc Acd under Yressure 5 The expermental apparatus and procedure at hgh pressure are the same as n the reports of Ths joasrtaal."' t01 About 0.8 gr of Malec acd n the pressure~proof vessel was preheated at about 120`C before the compressng procedure and controlled at the fxed temperature n a few mnutes after the defnte pressure was appled. A few per cent of Malec acd was somerzed to fumarc acd durng the manpu laton above descrbed. The values are shown n Table 1, beng wthn 0.1 per cent Table 1 ntal concentraton n per cent Temp. C ] O.A b2 <0.1 le~ 7.7 ]: O.f 17a f 2.f below 145' C. They were used as the ntal concentraton of the somerzaton. (8) Determnaton of fumarc acd. The amount of Malec acd somerzed to fumarc acd lvas determned quanttatvely as follows ~='-`s' Fumarc acd slghtly soluble s much less soluble n water than Malec acd. The solubltes"" n 100 gr water of fumarc and Malec acds are 0.70 artd 78.8gr at 25 C respectvely. A defnte volume of a saturated aqueous soluton of fumarc acd (0.035 M at G` C)f ' was poured nto an unknown sample of a mxture of Malec and fumarc acds, and Malec acd was completely dssolved after mmersng n an ce-water bath for about 5 hours. The nsoluble fumarc acd was fltered off wth a sucton nn a small glass flter and carefully washed two or three tmes wth a defnte volume of a sattuated aqueous soluton of fumarc acd at 0` C. The fltrate was ttrated wth about 0.1 N standard alkal, usng a phenolph talen ndcator. The quantty of fumarc acd added to the soluton of the sample and ts fltrate were corrected. More than 0.8 mllgrammes of fumarc acd could be detected by ths method. Expermenkal Results. The transton, under the condtons of temperatures 125 ^-175 C, pressures 1 2,250 atm and reacton tme 1/2 hour, s shown n Table 2 and Fg. 1. Every sotherm has an nflexon pont whch shfts to hgh temperature wth ncrease n pressure. Malec acd s somerzed n the lyuld state fastly tll the pont and n the sold state slowly after the pont. The dagram between the per cent of fumarc acd somerzed and the temperature s plotted n Fg. 2 from Table 2. The nflexon (9) R. Kyama, Tks jo~nnat, 19, (1945) (10) R. Kyama and T. Yanagmoto, bd., 21, 3? (7901) (11) nt. Crt. Table, vol. 4, 25 (1928)

4 The Revew of Physcal Chemstry of Japan Vol. 22 No 1 (1952) G R Kyama and S. Mnomwa Table 2 Transton per cent n 1/2 how TempP C 1l5 135 Atmos. Press. 0:9 9l gso ~ soa 4.g $ <0.7 OS zf f+5 1' ~ a5.8 G , o. 'm s ~ ao so 40 7Q Q Rcartron ' 7 J~~ ld5 :rj3~ 45 ~. t35.. o~.'j~~..~/ 2 ~_ tme: /~ u Pressure (atm) rs. 1 hour 175 U 1~ v u l25 a Qtmos. ~~. 'o 900 press. O JSO ~ 1800 ~o?z50 atm ly 00 'L250 0 ZO SO 100 Component % (fumarc acd) Fg. 2 pont., o. 0.y G A ['/ loo of So r sa ( every sobar shows 125D atm ~yso -atm Qtmos. press. 9~ og ~t SC /S C 'L 4 Pg.3 Tme _ C+ (hour) the meltng pont of the mxture of varous component!7s C 9 SO rato under pressure and temperature wth ncrease Hour The transtons 1/2 1 2 Atmos. Press. n the Table 3 shfts n pressure. scaled Transton 0 at 175 C 45.7 f.2 &5.4 _~ 450 ~,~.~ s~.n to hgh tube at 2250 G ,

5 The Revew of Physcal Chemstry of Japan Vol. 22 No. 1 (1952) Cs-Traps somerzaton of Malefc Acd to Fumarc Acd under Pressure C, and under 450 and 2,250 atm at 175 C are shown n Fg. 3 and Table 3. The somerzaton n the sealed tube was not found n 6 hours at 100 C and below 0.1 per cent at 110 C. 1'he curve at 125 C has an nflexon pont at the ntal stage of somerzaton. Malefc acd s stll n the sold state tll the pont smlarly as the sold state at 115 C and melts partally wth fumarc acd after the pont Malefc acd melts completely n the course of somerzaton as at 135 and 175 C and svpersaturated fumarc acd s gradually depostted. The curve at 135 C reaches nearly equlbrum n 10 hours. The transton under pressure at 175 C results n lttle ncrease wth pressure. Dscussons. The man expermental results obtaned above can be summarzed as follows: (1) Every sotherm has an nflexon pont whch shfts to hgh temperature wth ncrease n pressure. Malefc acd s somerzed n the lqud state tll the pont and n the sold state after the ponk (Fg. 1) (2) The rate of transton ncreases wth pressure tll the nflexon pont, but decreases after the pont. (Fg. 1) (3) The amount of transton at the fxed temperature for a few hours results n lttle ncrease wth pressure. (Fg. 3) The meltng pont of a materal shfts to hgh temperature wth ncrease n pressure. The values of a number of materals under pressure have been measured by Brdgnlan1B' and arc found n nk Crk Table, vol. 9, p. 9, n whch are gven the two constants of the parabolc formula t-t =ap+bp=, n terms of whch Tammann was able to reproduce hs results. The rate of transton ncreases wth pressure, so long as malefc acd melts, but t decreases n the sold state, as the meltng pont of malefc acd also shfts to hgh temperature wth ncrease n pressure. The effect of pressure of chemcal equlbrum s gven by the general expresson, (~l _~`, (1) ` BPJr where G s Gbbs's free energy, P pressure and V moleculaz volume. And R n KadT= dg (2 ) where Ka s the equlbrum constant under a constant pressure and gven by ([fumarc acd]/(malefc acd])egnt. and dg s the dfference of the free energy between fumarc and malefc acds. From equatons (1) and (2), dlnk,. dv '16' "" (12) P. W. 13rdgman, "The Physcs aj Hgh Pressure;' London, chap. 7 (1949) (13) M. G. Evans and M. Polany, Trans. Fnrad: Soc., 31, 875 (1935), 32, 7333 (193('+), 33, 448 (1936) (19) M. G. Evans,-tYA., (1938)

6 The Revew of Physcal Chemstry of Japan Vol. 22 No. 1 (1952) 8 t Kyama and S. Mnomura where dv s the dfference of the moleculaz volume betweenfumarc and malec acd and dependent on temperature and. pressure, When t s postulated that dv results n lttle change wth ncreases n temperature and pressure, the equaton, r s obtaned from the ntegraton. of equaton (3) and expresses the effect of pressure on the equlbrum: The molecular volumes of funtarc and malec acds calculated from the denstes"" at 20 C under atmospherc pressure are and cc/mole respectvely. The dfference s cc/mole. The somerzaton at 175' C under atmospherc pressure calculated from equaton (9) to the transton (95.0 b) for 9 hours under 2,250 atm, s 99.9 ' n accordance wth the experment. The authorsarendebted to the Department of Educaton for the Grant to the Cooperatve Research (1'he Fundamental Research on Hgh Pressure ndustres). Th Laboratory of Physcal Cltemsfly, Kyofo Unversfy. (]5) C. D. Hodgman, "Handbook of CGemstry m,d Physcs", Cleveland, Oho, p. F83, 719 (1939)

Title solubility of compressed acetylene.

Title solubility of compressed acetylene. Ttle The solubltes of compressed acet solublty of compressed acetylene Author(s) Hraoka, Hroyuk Ctaton The Revew of Physcal Chemstry of 18 ssue Date 1954-09-10 URL http://hdl.handle.net/2433/46704 Rght