一道大学化学题目,大神帮帮忙!
某水溶液的凝固点为-0.303℃,试求该溶液25℃时的蒸汽压合渗透压。已知H2o的Kf=1.86K*KG/mol,25℃时纯水的饱和蒸汽压为3.17kPa...
某水溶液的凝固点为-0.303℃,试求该溶液25℃时的蒸汽压合渗透压。已知H2o的Kf=1.86K*KG/mol,25℃时纯水的饱和蒸汽压为3.17kPa
展开
展开全部
(1)由拉乌尔定律:
△T = b Kf
b = △T / Kf = 0.303 / 1.86 = 0.1629 (mol / kg水)
1000克溶剂的物质的量:1000/ 18 = 55.6 mol
溶剂的摩尔分数:55.6 / (55.6+ 0.1629 )= 0.997
P(溶液) = P(纯溶剂) * 溶剂摩尔分数
= 3.17 * 0.997
= 3.16
(2)渗透压π
π V = nRT
π = CRT≈ b R T = 0.1629 * 8.314 * 298 = 403.6 (kPa)
△T = b Kf
b = △T / Kf = 0.303 / 1.86 = 0.1629 (mol / kg水)
1000克溶剂的物质的量:1000/ 18 = 55.6 mol
溶剂的摩尔分数:55.6 / (55.6+ 0.1629 )= 0.997
P(溶液) = P(纯溶剂) * 溶剂摩尔分数
= 3.17 * 0.997
= 3.16
(2)渗透压π
π V = nRT
π = CRT≈ b R T = 0.1629 * 8.314 * 298 = 403.6 (kPa)
推荐律师服务:
若未解决您的问题,请您详细描述您的问题,通过百度律临进行免费专业咨询