Suppose that scientists have discovered a new compound on a different planet whose elements are different from those of those earth. The scientists find that the compound has the formula X2O7 where X is a special element and O is normal earth oxygen.
a. What is the oxidation state of X in this compound?
b. Suppose it is found that X2O7 dissolves quite well in water by dissociating. What type of bond do you think exists in X oxide? Justify your answer.
c. Explain what properties of water make it able to dissolve X oxide.

Question

Suppose that scientists have discovered a new compound on a different planet whose elements are different from those of those earth. The scientists find that the compound has the formula X2O7 where X is a special element and O is normal earth oxygen.
a.	What is the oxidation state of X in this compound?
b.	Suppose it is found that X2O7 dissolves quite well in water by dissociating. What type of bond do you think exists in X oxide? Justify your answer.
c.	Explain what properties of water make it able to dissolve X oxide.

anonymous · Answer

a) +7
b) If the compound dissociates in water then all bonds must be polar bonds so by extension the compound should also be an ionic substance, this can be found using the electronegativity of each constituent atom.
c) Waters molecules contain 2 polar bonds at an angle not equal to 180° so overall the water molecule is polar, because like dissolves like, the polar water molecule will only dissolve (not incl. sparingly soluble) and cause other polar compounds to dissociate.