Calculate the number of atoms in 20 g of a m | vedclass

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(B) For a simple cubic structure, the number of atoms per unit cell, $Z = 1$.The density formula is $d = \frac{Z 	imes M}{a^3 	imes N_A}$.Given: $d

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$5.19 	imes 10^{22}$

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(B) For a simple cubic structure, the number of atoms per unit cell, $Z = 1$.The density formula is $d = \frac{Z 	imes M}{a^3 	imes N_A}$.Given: $d = 9.8 \ g \ cm^{-3}$, $a = 340 \ pm = 3.40 	imes 10^{-8} \ cm$, $N_A = 6.022 	imes 10^{23} \ mol^{-1}$.Substituting values: $9.8 = \frac{1 	imes M}{(3.40 	imes 10^{-8})^3 	imes 6.022 	imes 10^{23}}$.$M = 9.8 	imes (3.9304 	imes 10^{-23}) 	imes 6.022 	imes 10^{23} \approx 231.97 \ g \ mol^{-1}$.Number of moles in $20 \ g = \frac{20}{231.97} \approx 0.08622 \ mol$.Number of atoms $= 	ext{moles} 	imes N_A = 0.08622 	imes 6.022 	imes 10^{23} \approx 5.19 	imes 10^{22}$ atoms.

Calculate the number of atoms in $20 \ g$ of a metal which crystallizes in a simple cubic structure with a unit cell edge length of $340 \ pm$. (Density of metal $= 9.8 \ g \ cm^{-3}$)

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