无水钾镁矾类复盐(A^+)_2Cd_2(SO_4)_3的热化学  

Thermochemical Studies on the Langbeinite-Type Double Sulfate Salts，(NH_4)_2Cd_2(SO_4)+_3 and K_2Cd_2(SO_4)_3*

作　　者：周亚平[1] 张瑞[1] 万洪文[1] 詹正坤[1] 许名飞[1] 

机构地区：[1]华中师范大学化学系,武汉430079

出　　处：《物理化学学报》2001年第3期245-247,共3页Acta Physico-Chimica Sinica

基　　金：湖北省科委九五攻关!(No.630-230896) &&

摘　　要：The standard molar formation enthalpies of （A＋）2Cd2（SO4）3[A＋is NH-4＋or K＋ ] are determined from the enthalpies of dissolution （ΔSHm） of [（A＋）2SO4（s）＋ 2CdSO4（s）] and （A＋ ）2Cd2（SO4）3（s） in twice distilled water or 3 mol· L－ 1 HNO3 solvent respectively,at 298.2 K,as: Δ fHm[（NH4）2Cd2（SO4）3,s,298.2K]=－ 3031.74± 0.08 kJ· mol－1 Δ fHm[K2Cd2（SO4）3,s,298.2K]=－ 3305.52± 0.17 kJ·The standard molar formation enthalpies of (A(+))(2)Cd-2(SO4)(3)[A(+) is NH4+ or K+] are determined from the enthalpies of dissolution (Delta H-s(m),) of [(A(+))(2)SO4(S) +2CdSO(4)(s)] and (A(+))(2)Cd-2(SO4)(3)(s) in twice distilled water or 3 mol . L-1 HNO3 solvent respectively, at 298, 2 K, as: Delta H-f(m)circle minus[(NH4)(2)Cd-2(SO4)(3), s, 298.2K] = -3031.74 +/- 0.08 kJ . mol(-1) Delta H-f(m)circle minus[K2Cd2(SO4)(3), s, 298.2K] = -3305.52 +/- 0.17 kJ . mol(-1).

关 键 词：硫酸复盐 溶解量热法 标准摩尔生成焓 热化学 无水钾镁矾类复盐 

分 类 号：O642[理学—物理化学]