● 代入上式，得： ● xB=△fusHm(△T/RTT)≈△usHm△TR(Tr)2 △TFR(Tf)2/△sHm·xg (1) ● ≈R(Tf)2/△usHm'(ng/nA) ● =MAR(Tf*)2/△usHm∵(ngW)m ● △T=KmB (2) KFR(Tf)2/△fusHmMA (3) ·K:溶剂凝固点降低常数(cryoscopic constant); 单位：K.kg.mol1. ·K的值只与溶剂的性质有关，与溶质的性质无关 • 代入上式,得: • xB =fusHm(T/RTfTf * )≈fusHmTf /R(Tf * ) 2 • Tf=R(Tf * ) 2 /fusHm· xB (1) • ≈R(Tf * ) 2 /fusHm· (nB /nA) • =MAR(Tf * ) 2 /fusHm· (nB /WA) =mB • Tf=KfmB (2) • Kf=R(Tf * ) 2 /fusHm·MA (3) • Kf :溶剂凝固点降低常数(cryoscopic constant); 单位: K.kg.mol-1 . • Kf的值只与溶剂的性质有关,与溶质的性质无关