Crystals structures can also be seen when two elements combines together and the perfect example is Al₂O₃ which is given in the question above. Just like it is given in the question above, the kind of arrangement in the crystal structure for Al₂O₃ is called HCP which stands for Hexagonally Closed Pack.
The aluminum ions which is in form of Al³⁺ occupies the two-third[2/3] positions while the position that the oxygen ion occupies is one[1].
Using Charles' law, which is V1/T1=V2/T2, we can plug in these numbers to find the answer. The law states that volume is directly proportional to temperature. 3.0L/100K = x L / 250 K. Solve for x to get 7.5 L. Hope this helps.
