Mass of fatty acid =0.027g in 10ml solution
Density of fatty acid 0.9 g/cc
Volume of fatty acid =0.90.027=0.03cc
Area of plate =πr2=3×102=300cm2
Height of fatty acid layer =areavolume=3000.03=10−4cm = 10−6m
0.27g of a long chain fatty acid was dissolved in 100cm3 of hexane. 10mL of this solution was added dropwise to the surface of water in a round watch glass. Hexane evaporates and a monolayer is formed. The distance from edge to centre of the watch glass is 10cm . What is the height of the monolayer?
[Density of fatty acid =0.9gcm−3;π=3]
Held on 8 Apr 2019 · Verified 6 Jul 2026.
10−4m
10−6m
10−8m
10−2m
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