A metal crystallises in BCC lattice with unit cell edge length of 300 pm and density 6.15 g cm-3 . The molar mass of the metal is

Question

A metal crystallises in BCC lattice with unit cell edge length of 300 pm and density 6.15 g cm-3 . The molar mass of the metal is (A) 50 g mol -1 (B) 60 g mol -1 (C) 40 g mol -1 (D) 70 g mol -1

Tardigrade Admin · Accepted Answer

d =( ZM / a 3 N A ) 6.15=(2 × M /(3 × 10-8)3 × 6.02 × 1023) M =(6.15 × 27 × 10-24 × 6.02 × 1023/2) M =50 g / mol

Q. A metal crystallises in $BCC$ lattice with unit cell edge length of $300 p m$ and density $6.15 g c m^{- 3}$ . The molar mass of the metal is

$50 g m o l^{- 1}$

$60 g m o l^{- 1}$

$40 g m o l^{- 1}$

$70 g m o l^{- 1}$

$d = \frac{ZM}{a ^{3} N _{A}}$
$6.15 = \frac{2 \times M}{( 3 \times 1 0 ^{- 8} ) ^{3} \times 6.02 \times 1 0 ^{23}}$
$M = \frac{6.15 \times 27 \times 1 0 ^{- 24} \times 6.02 \times 1 0 ^{23}}{2}$
$M = 50 g / m o l$

Q. A metal crystallises in BCC lattice with unit cell edge length of 300pm and density 6.15gcm−3 . The molar mass of the metal is

50gmol−1

60gmol−1

40gmol−1

70gmol−1