Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
10 mL of 1 mM surfactant solution forms a monolayer covering 0.24 cm2 on a polar substrate. If the polar head is approximated as a cube, what is its edge length?
ChemistrySurface ChemistryJEE MainJEE Main 2019 (09 Apr Shift 2)
Options:
  • A 1.0 pm
  • B 0.1 nm
  • C 2.0 pm
  • D 2.0 nm
Solution:
1116 Upvotes Verified Answer
The correct answer is: 2.0 pm
Millimoles of surfactants =10×10-3=10-2
Moles of surfactants =10-5
Number of molecules =6×1023×10-5=6×10+18
Surface area occupied by one molecule =0.246×1018=0.04×10-18cm2
4×10-20=a2
a=2×10-10cm=2pm

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.