Are you sure it isn’t SO3+H2O = H2SO4 because that would be combination (synthesis) A+ B=AB
Or SO3 + H2SO4 = H2S2O7
Because that would also be synthesis
The correct Answer based on my calculations is C
Answer:

Explanation:
As can be seen in the Figure in a face-centered cubic unit cell you have:
- Six halves of atoms
- Eight 1/8 of atom (1 in each corner)
In total:

Now, each side of the cell is 234 picometers (2.34e-8 cm) long


Atoms per cm3:


Expressing in mass:


It is an inorganic<span> compound
hope this helps
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