(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Calculate the radius of a palladium atom, given that Pd has an FCC crystal structure, a density of 12.0g/cm3, and an atomic weight of 106.4g/mol

2. Relevant equations

Pd contains 4 atoms per unit cell.

unit cell edge lengh = 2*Radius*sqrt(2)

3. The attempt at a solution

calculate atom weight:

106.4/6.0221418e23 = 1.7668133e-22

calculate unit cell weight:

1.7668133e-22*4 = 7.0672532e-22

calculate unit cell volume in cm3:

7.0672532e-22/12 = 5.8893777e-23

convert to nm3:

5.8893777e-23*(10^7)^3 = 0.0588938

calculate edge length:

0.0588938^(1/3) = 0.3890659

calculate radius:

0.3890659/2 = 0.194533

my answer:

0.194533nm

correct answer:

0.138nm

I cant figure out what i've done wrong here.

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# Homework Help: Calculating atomic radius from weight + density

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