Answer:
Explanation:
So, the formula for the compound should be:

Now we assume that we have 1 mol of substance, so we can make calculations to know the molar mass of element X, as follows:

So we have that 6 moles weight 212.7g, and we can make a rule of three to know the weight of compound X:

As we used 1 mol, we know that the molar mass is 32.06g/mol
So the element has a molar mass of 32.06 g/mol and an oxidation state of +6, with this information, we can assure that the element X is sulfur, so the compound is 
Explanation:
(1) Nuclear reactions involve a change in an atom's nucleus, usually producing a different element. Chemical reactions, on the other hand, involve only a rearrangement of electrons and do not involve changes in the nuclei. ... (3) Rates of chemical reactions are influenced by temperature and catalysts.
The answer is -3, if you are asking for that
A. The fact that it's less dense than cold air.