UPSC Combined Geo-Scientist, Mains · 2023 · Mains Paper II
Q8. Atomic weight of ¹⁵N from the rotational lines of NO
Question
The rotational absorption of ¹⁴N¹⁶O is observed at 50121.15 Hz and that of ¹⁵N¹⁶O at 48375.05 Hz. Calculate the atomic weight of ¹⁵N. [Mass of ¹⁴N = 14.007; mass of ¹⁶O = 15.9994]
Answer in brief
m(¹⁵N) = 14.99 u ≈ 15.0 u.
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Coversrotational spectroscopyisotope effectreduced massrigid rotormicrowave spectrum of NO