The shell which is before the valence shell is called the penultimate shell. If 'n' is the valence shell then (n-1) is the penultimate shell.
Electronic configuration of S(sulphur) = 2. 8. 6.
so,
Number of e- in valence shell=6
Number of e- in penultimate shell=8
The tungsen filament for electric bulb is formed by