Answer:
D. Crystallization
Explanation:
Let's clarify the irrelevant terms first.
- unification: This term has nothing to do with chemistry at all
- lithification: When the problem mentions magma and lava, you might think that this term is related to the process here. However, 'lithification' <em>do </em>have a precise meaning in geology. It refers to the process where sediments collapses into one single rock under pressure, which has nothing to do with the process mentioned here.
Now, for 2 terms that might confuse you: 'solidification' and 'crystallization' these also has precise scientific definition
Solidification is defined the process where substances in <em>liquid</em> phase changes its phase to <em>solid</em>. On first glance, this answer might seems correct, and yes, it is correct for this question. But not the <em>most</em> correct.
The keyword here is
'the internal components will arrange its self in an organized pattern.'
Crystallization is a special case of Solidification where the atoms or molecules of liquid solidify by spontaneously arrange themselves in periodic, ordered, and organized pattern. It might or might not happen during solidification depending on cooling rate, viscosity of liquid, and other factors.
So, Crystallization is the most correct answer here.
The formula for mole fraction is:
-(1)
The solubility of oxygen gas = 1.0 mmol/L (given)
1.0 mmol/L means 1.0 mmol are present in 1 L.
Converting mmol to mol:

So, moles of oxygen = 0.001 mol
For moles of water:
1 L of water = 1000 mL of water
Since, the density of water is 1.0 g/mL.


So, the mass of water is 1000 g.
Molar mass of water = 18 g/mol.
Number of moles of water = 
Substituting the values in formula (1):


Hence, the mole fraction is
.
so you can see those fluorine atoms have really spread out around the central phosphorus atom. this gives us a trigonal bi-pyramidal molecular geometry for pf5.