As shown schematically in the figure, two vessels contain water solutions (at temperature 𝑇) of potassium permanganate (KMnO4) of different concentrations 𝑛1 and 𝑛2 (𝑛1 > 𝑛2) molecules per unit volume with Δn=n1−n2≪n1 . . When they are connected by a tube of small length ℓ and cross-sectional area S, KMnO4 starts to diffuse from the left to the right vessel through the tube. Consider the collection of molecules to behave as dilute ideal gases and the difference in their partial pressure in the two vessels causing the diffusion. The speed v of the molecules is limited by the viscous force −βv on each molecule, where β is a constant. Neglecting all terms of the order (Δn)2, which of the following is/are correct? (𝑘𝐵 is the Boltzmann constant)-
see full answer
High-Paying Jobs That Even AI Can’t Replace — Through JEE/NEET
🎯 Hear from the experts why preparing for JEE/NEET today sets you up for future-proof, high-income careers tomorrow.
An Intiative by Sri Chaitanya
a
the force causing the molecules to move across the tube is ΔnkBTS
b
force balance implies n1βvℓ=ΔnkBT
c
total number of molecules going across the tube per sec is ΔnℓkBTβS
d
rate of molecules getting transferred through the tube does not change with time
answer is A.
(Unlock A.I Detailed Solution for FREE)
Best Courses for You
JEE
NEET
Foundation JEE
Foundation NEET
CBSE
Detailed Solution
PV=NkBT⇒P=NVkBT=nkBTn1>>n1−n2=Δn F=P1-P2S=n1−n2kBTS=ΔnkBTSOption (A) is correct.Viscous Force = Total number of molecules ×βv=n1lSβvIf viscous force is balanced by pressure force, then ΔnkBTS=ℓn1Sβv⇒n1βvℓ=ΔnkBT Option (B) is correct. Total number of molecules per sec=n1vdtSdt=n1vS=ΔnkBTvSβvℓ=ΔnℓkBTβSOption (C) is correct.As ∆n will decrease with time therefore rate of molecules getting transfer decreases with time.Option (D) is incorrect.