UPSC Combined Geo-Scientist, Mains · 2024 · Mains Paper II
Q3(b). Atomic mass of a bcc element from density and cell edge
Question
A bcc element of density 10300 kg m⁻³ has a cell edge of 314 × 10⁻¹² m. Calculate the atomic mass of the element.
Answer in brief
M = 0.0960 kg mol⁻¹ = 96.0 g mol⁻¹: the element is molybdenum.
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Coversbody-centred cubicunit cell densityρ = ZM/NAa³atomic massmolybdenum
All parts of Question 3
- 3(a) Miller indices of the plane (2a, −3b, −3c)3 marks
- 3(b) Atomic mass of a bcc element from density and cell edge7 marks