Did the person who wrote this problem even try solving it?  It's actually not solvable with the information given.  When I tried it, I actually got more xylene than is actually present, when I added the three amounts together. Partly, this is because you were given the wrong Henry's...

Oops.  Did it again.  That should have been added as an answer, rather than a comment.  Too bad I can't remove, or even edit my comment.

The octet rule isn't really a reason why.  It's simply an observation as to what happens.  The full answer is rather complex, but it mainly amounts to two properties:  ionization energy (how much energy it takes to remove an electron) and electron affinity (the ability to gain electrons)...

Correct answer:  None of the above Probable expected answer:  benzene As Daniel stated, a secondary carbon has two adjacent carbons (benzene is the only one that fits). However, there is another aspect of the definition, in that the term is only used for tetrahedral (sp3) carbons...

The mass number is not the same as the mass of the atom. The mass number is obtained by counting the number of protons and neutrons. Each proton and neutron is approximately 1 u, but not exactly.  Also, in atoms, the total is not the sum of the parts.  A small amount of mass...

What, exactly, are you asking? Is what true? This is very convoluted. There are errors in the calculations above: line 2, the mass of an atom of Li is 6.94 u, but close enough line 7, remove the "kg" from the end. line 9, put parentheses around the denominator, otherwise...

The first answer is incorrect.  At the stoichiometric point, the concentration of the NH3 is almost zero (all of the NH3 has reacted with H+).  To a first approximation, it is zero.  All that's present is NH4+ (plus the NO3- spectator ions, which we'll ignore).  Since...

Here are two other aspects to this phenomenon. The "seal" referred to above is caused by the fact that water is attracted to both the surface and the glass.  When you attempt to lift the glass, the water seal is kept in place initially.  When this happens, you are attempting...

Can you clarify the question?