Helium gas diffuses 4 times as fast as an unknown gas. What is relative molecular mass of the gas

The relative molecular mass of the gas : 64 g/mol

Given

Helium rate = 4x an unknown gas

Required

The relative molecular mass of the gas

Solution

Graham's Law

r₁=4 x r₂

r₁ = Helium rate

r₂ = unknown gas rate

M₁= relative molecular mass of Helium = 4 g/mol

M₂ = relative molecular mass of the gas

Input the value :

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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