英文化学题 有人会做么

来源：百度知道 编辑：UC知道 时间：2024/06/06 19:11:06
the solution is made up of 5g of an unknown solid in 100g of bromoform（kf=14°C/m).
the solution has a freezing point 4°C lower than the freezing point of bromoform. what is the molar mass of the unknown solid?

这是物理化学中凝固点降低法测摩尔质量的题

根据稀溶液的依数性，有公式：

Mb=Kf(Wb/ΔTf*Wa)= 14(5/4*100)=0.175 kg/mol

Kf 的单位应是℃ kg/mol

the molar mass of the unknown solid=175g/mol