凝固点降低计算器
计算溶质引起的溶液凝固点降低值。
C-kg/mol
m
C
Freezing Point Depression
1.860 C
New Freezing Point-1.860 C
Freezing Point Depression vs Cryoscopic Constant (Kf)
公式
## How to Calculate Freezing Point Depression ### Formula **delta_Tf = i × Kf × m** For water, Kf = 1.86 C-kg/mol. New FP = pure FP - delta_Tf.
计算示例
0.5 m NaCl (i=2) in water.
- 01delta_Tf = 2 × 1.86 × 0.5 = 1.86 C
- 02New FP = 0 - 1.86 = -1.86 C
常见问题
What is freezing point depression?
A colligative property where dissolving a solute lowers the freezing point. This is why salt is spread on icy roads.
Why is Kf larger than Kb for water?
The enthalpy of fusion is smaller than the enthalpy of vaporization, making freezing point more sensitive to solute.
Does this work for all solvents?
Yes, but each has its own Kf. Cyclohexane Kf = 20.0, making it useful for precise molar mass determinations.
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