What does molten rock solidify into? a. basalt b. marble c. ...

[dejastew]

What does molten rock solidify into?
 
  a. basalt
 b. marble
 c. sandstone
  d. quartzite
 e. travertine

Question 2

What are forbidden lines? Briefly describe how they form.
 
  What will be an ideal response?

[leeeep]

Answer to Question 1

a

Answer to Question 2

Forbidden lines are certain lines in the spectra of emission nebulae that are never seen in the spectra of excided gas. When excited gas jumps between certain energy levels, it happens very quicklyin the order of 10-8 to 10-7 seconds. On rare occurrences, electrons get stuck in one of these metastable levels before it falls to a lower level and emits a photon of the corresponding energy. Unless the gas has extremely low density, collisions between atoms will disturb electrons caught in metastable levels long before they can make a transition downward and emit a photon producing forbidden lines.

[dejastew]

Great answer, keep it coming

[Bigfoot1984]

Thanks for the timely response, appreciate it