Copper crystallises in a face-centred cubic lattice with edge length 360 pm. Taking M = 63.5 g mol^-1 and N_A = 6.022x10^23 mol^-1, calculate the density of copper in g cm^-3 (two decimals).

JEE Main levelNumerical answerDifficulty 2 of 3ss012

Copper crystallises in a face-centred cubic lattice with edge length $360 pm$ . Taking $M = 63.5 g mo l^{- 1}$ and $N_{A} = 6.022 \times 1 0^{23} mo l^{- 1}$ , calculate the density of copper in $g c m^{- 3}$ (two decimals).

Numerical answer type, answer in g/cm^3, tolerance 0.02.

For fcc

Z = 4

, and

ρ = \frac{ZM}{N _{A} a ^{3}}

. With

a = 3.60 \times 1 0^{- 8} cm

a^{3} = 4.6656 e - 23 c m^{3}

. Hence

ρ = \frac{4 \times 63.5}{6.022 \times 1 0 ^{23} \times 4.6656 e - 23} \approx 9.04 g c m^{- 3}