8.12 Two transitions in the [Ne] 3p¹→[Ne]3s' emission spectrum of atomic sodium are observed at 589.0 nm and 589.6 nm. What is the difference in energy, expressed in elec- tronvolts, between the 2P 3/2 and 2P 1/2 levels of the upper term?

The electronic structure of one-dimensional chain of sodium (Na) atoms can be approximately described by the particle-in-a-box model. The energy of each state can be calculated using n?h? En 8mlz п 3 1,2, 3, ... where L is the length of the 1D chain. Assuming L = ao(N – 1), where N is the number of Na atoms and ao = 0.360 nm is the internuclear distance. a) Determine the energy gap between the highest occupied energy level and the lowest unoccupied energy level as a function of N. Assume that N is an even number that is large enough b) Thermal energy at room temperature is 4.15 × 10-21 J. Calculate the minimum number of Na atoms required so that the energy gap is smaller than the thermal energy.

Kk.92.

Which of the following transitions between terms are allowed in the electronic emission spectrum of a many-electron atom: (i) 3D2 → 3P1, (ii) 3P2 → 1S0, (iii) 3F4 → 3D3?

8.1(a) Calculate the energy separations in joules, kilojoules per mole, electronvolts, and reciprocal centimetres between the levels (a) n= 2 and n= 1, (b) n=6 and n=5 of an electron in a box of length 1.0 nm.

Predict the ground-state electronic configuration of (a) a C atom. (b) a Ti2+ ion. and (c) a Mn2+ ion.

Give the possible term symbols for (i) Li [He]2s1, (ii) Na [Ne]3p1.

Consider the three electronic transitions in a hydrogen atomshown here, labeled A, B, and C.(a) Three electromagnetic waves, all drawn on the samescale, are also shown. Each corresponds to one of thetransitions. Which electromagnetic wave (i), (ii), or (iii),is associated with electronic transition C?

Only certain electron transitions are allowed from one en-ergy level to another. In one-electron species, the change in the quantum number l of an allowed transition must be ±1. For ex-ample, a 3p electron can drop directly to a 2s orbital but not to a 2p. Thus, in the UV series, where nfinal1, allowed electrontransitions can start in a porbital (l=1) of n=2 or higher, notin an s(l=0) or d(l=2) orbital of n=2 or higher. From whatorbital do each of the allowed electron transitions start for the first four emission lines in the visible series (n(final=2))?

What is the answer