The most likely bond between element X and Iodine would be an ionic, or electrovalent, bond. Iodine has seven electrons in its outer shell, also known as the valence shell. To become perfectly stable, it needs only a single electron from another element. Hence no sharing of electron takes place (usually), which is the condition required for it to be covalent bonding. Hence it's most likely an ionic bonding/
freezing. Think of what happens when you put water in the freezer
There are several information's already given in the question. Based on the information's the answer can be easily deduced.
We know the formula
<span>P1*V1/T1 = P2*V2/T2
</span>
As the temperature is constant, so T1 and T2 can be negated. The formula changes to
<span>P1*V1 = P2*V2
</span>70 * 1 = 540 * V2
270/540 = V2
<span>V2 = 0.5
</span>
From the above deduction, we can conclude that the new volume is 0.5 liters. I hope that the procedure is clear enough for you to understand.