[HCOOH]=0.5mlL−1
⇒(0.5ml×1.05gml−1)HCOOH in 1L
⇒0.525gHCOOH in 1L
Weight of water will be =1kgsincedensityofwateris1kg/L
m=1kg(460.525)mol [Assuming dilute solution]
∴ΔTf=iKfm⇒i=kfmΔTf=1.86×0.5250.0405×46=1.9
The depression in freezing point observed for a formic acid solution of concentration 0.5mLL−1 is 0.0405∘C. Density of formic acid is 1.05gmL−1. The Van't Hoff factor of the formic acid solution is nearly: (Given for water kf=1.86Kkgmol−1)
Held on 25 Jul 2022 · Verified 6 Jul 2026.
0.8
1.1
1.9
2.4
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