a) Write the balanced equation (not the mechanism) for the protonation ofnitric

Question

a) Write the balanced equation (not the mechanism) for the protonation ofnitric acid by sulfuric acid, represented as an equilibrium expression.

b) Write the equilibrium constant expression for the reaction shown in part(a) above.

c) Consider the pKa values shown below:

H2SO4: -3

HSO4-: +2

HNO3: -1.3

H2NO3+: -13

Based on these pKa values, determine the equilibrium constant for thereaction that you wrote down for part (a).

Question #2:The proton NMR spectrum of chlorobenzene was examined by Hiyamizu andcoworkers in 1968. Their analysis revealed the following chemical shifts.The hydrogens ortho to the chlorine are at 7.28 ppm.The hydrogens meta to the chlorine are at 7.23 ppm.The hydrogen para to the chlorine is at 7.16 ppm.

a) Start by using arrow formalisms to draw resonance structures ofchlorobenzene using the chlorine as an electron donor. (2 points)b) One might expect that the positions that have negative charges (andhence excess electron density) in the resonance structures would be themost upfield, but this is not the case. Explain why, and explain why thechemical shifts appear where they do relative to each other.

Explanation / Answer

a) HNO3 + H2SO4 <----------> H2NO3+ + HSO4-

b) If the pKa are those, then the equilibrium constant it would be:
Kc = (10(13)) * 10(-2) / (10(1.3)) * (10(3))
Kc = 1x10-11 / 1.995x104
Kc = 5.01x10-16

Now the resonance structures, I know how to do them, but I do not how to explain the chemical shift in the NMR spectrum cause I don't have knowledge of that. Post that question in another post.

Hope this helps

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