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find no of atom

Asked by ashutosharnold1998 | 16 Apr, 2020, 11:25: AM

Expert Answer

Given:

Mass of crystal = 100 gm

Density, Ρ = 10 gcm^-3

Edge length, a = 100 pm

We know,

straight rho space equals fraction numerator straight Z cross times straight M over denominator straight a cubed cross times straight N subscript straight A end fraction straight M space equals space fraction numerator straight a cubed cross times straight N subscript straight A cross times straight rho over denominator straight Z end fraction space space space space space equals fraction numerator open parentheses 100 cross times 10 to the power of negative 10 end exponent close parentheses cubed space cross times 6.022 cross times 10 to the power of 23 cross times 10 over denominator 4 end fraction space space space space space space equals space 1.5 space space gmol to the power of negative 1 end exponent

So 6.022 g/mol contains Avogadro's number of atoms

Therefore 100 gm will contain

fraction numerator 100 cross times 6.022 cross times 10 to the power of 23 over denominator 1.5 end fraction equals space 4 cross times 10 to the power of 25 space a t o m s

Answered by Varsha | 16 Apr, 2020, 01:06: PM

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