In orthorhombic unit cell the value of a , b and c are respectively 4.2 mathringA, 8.6 mathringA and 8.3 mathringA. Given the molecular mass of the solute is 155 g mol -1 and density is 3.3 g / cc, the number of formula units per unit cell is (Report your answer by rounding up to nearest integer)

Question

In orthorhombic unit cell the value of a , b and c are respectively 4.2 mathringA, 8.6 mathringA and 8.3 mathringA. Given the molecular mass of the solute is 155 g mol -1 and density is 3.3 g / cc, the number of formula units per unit cell is (Report your answer by rounding up to nearest integer) (A) 2 (B) 3 (C) 4 (D) 6

Tardigrade Admin · Accepted Answer

Z =( V × N A × ρ/ M ) V= Volume of unit cell =a × b × c =(4.2 × 8.6 × 8.3 × 10-24 × 6.023 × 1023 × 3.3/155)=3.84 ∼ e q 4

Q. In orthorhombic unit cell the value of a,b and c are respectively 4.2A˚,8.6A˚ and 8.3A˚. Given the molecular mass of the solute is 155gmol−1 and density is 3.3g/cc, the number of formula units per unit cell is (Report your answer by rounding up to nearest integer)

2

3

4

6

Z=MV×NA​×ρ​ V= Volume of unit cell =a×b×c =1554.2×8.6×8.3×10−24×6.023×1023×3.3​=3.84∼eq4

$Z = \frac{V \times N _{A} \times ρ}{M}$
$V =$ Volume of unit cell $= a \times b \times c$
$= \frac{4.2 \times 8.6 \times 8.3 \times 1 0 ^{- 24} \times 6.023 \times 1 0 ^{23} \times 3.3}{155} = 3.84 \sim e q 4$