In harmonic oscillator approximation, the selection rule for vibrational transit
ID: 531129 • Letter: I
Question
In harmonic oscillator approximation, the selection rule for vibrational transitions is Delta v = plusminus 1. The extinction coefficient associated with n rightarrow pi* transition is significantly greater than that of pi rightarrow pi* transition Calculate the Doppler shift for radiation of 4.28 MHz, if the velocity of a molecule is 10^5 cm/s. A. 14.3 mu Hz B. 14.3 Hz C. 3.3 mu Hz D. 0.30 MHz E. 0.143 MHz Calculate the number of vibrational modes in the following molecule A. 3 B. 4 C.5 D. 1 E. 9 Which of the following statements about NMR is NOT TRUE? A. The value of nuclear magneton (mu_N); does not depend on the nucleus. B. A proton chemical shift increases with the acidity of the proton. C. NMR spectra can only be observed for molecules having protons. D. NMR spectroscopy can be employed to distinguish between structural isomers.Explanation / Answer
Ans. 13. N2O (linear)
N=3
No. of vibration modes = 3N-5 = 3 * 3 - 4 = 5
ans c ( =5)
Ans 14. A.
the value of nuclear magneton depend on the nucleus, If nucleus I = 1 then nuclear magneton value is 2mI + 1