Question

i need a solution for these provlems. plz~~

3) The vibrational energy of a carbon monoxide, co, molecule in its first excited vibrational state is 3.42 x 10-20 J. Assuming that a carbon monoxide molecule may be treated as a harmonic oscillator with a force constant of k 2170 N m-1, calculate the classical amplitude of vibration for the molecule in this state. a. 5.61 nm *b. 5.61 pm c. 5.61 A d. 56.1 nm 4) The Rydberg constant for the Be3 on is 109731 cm Calculate the ionization energy of a ground-state Be3 On a. 218 eV b. 13.6 eV C. 54.4 eV d. 9.3 eV 5) To which orbitals may 5d electrons make spectroscopic transitions in a hydrogenic atom? a. ns and np b. np and nd C. ns and nd *d., np and nf

Answer 1

3) Ans b

Vibrational energy(E) = potential energy = $1/2kx^{2}$

$E=1/2kx^{2}$ where k=force constant, x = classical amplitude

   $x = \sqrt{2E/k} = \sqrt{2*3.42*10^{-20}/2170} = 5.61 * 10^{-12}m = 5.61 pm$

4) Ans a

where IE = ionization energy, R: rydberg constant, n1= 1 and n2= infinity, Z = atomic number Be3+ = 4

IE = 109731*4*4 [1-0]= 1755696 cm-1/8065 = 218 ev

5) Ans d

selection rule for orbital angular momentum

   $\Delta l =+/- 1$

for 5d , l = 2

possible transitions to l = 1 i.e p and l = 3 i.e f

therefor np and nf