Answer:
the answer is the second option
I believe the change of state shown in the model is deposition.
Deposition is a process in which gases change phase and turns directly in solids without passing through the liquid phase. It is the opposite of sublimation.
One of the major difference between gases and solids is the distance between molecules; in gases the inter molecular spaces are large, while in solid they are very small, making solids be the most dense, with closely packed molecules. This is evident in the diagram, the phase changed from gases to solids.
Answer:

Explanation:
The steps of the Ostwald process:



Combinning the equations:

+

+

=

Simplifying:


The overall reaction is endothermic becuase the formation of new chemical bonds requires energy consumption.
Answer:
B. their outer electron levels are filled
Answer:
=16.49 L
Explanation:
Using the equation
P1= 0.6atm V1= 30L, T1= 25+273= 298K, P2= 1atm, V2=? T2= 273
P1V1/T1= P2V2/T2
0.6×30/298= 1×V2/273
V2=16.49L