Question

Copper crystallises with fcc unit cell if the radius of copper atom is 127.8pm calculate density of copper metal atomic mass of cu 63.55u

Answer 1

Answer:

For fcc , Z = 4 , Atomic mass (M) = 63.554 , r = 127.8 pm , d = ? ?

Avogardo number NA=6.02×1023gmol−1

d=Z×Ma3×NA [In Fc. structure 2–√ a = 4 r]

a=4×r2–√=4×127.81.414=361.52 pm

d=4×63.556.02×1023×(3.61×10−8)3

d=0.89×101=8.9gmcm−3

Hope it helps u !!