I'll pay for chemistry tutoring...

I’ll actually send you money via PayPal or Venmo if you like, for good insight on these questions. I got AP Chemistry materials from a long time teacher who even grades the AP test, but I don’t want to bother him with asking for tutoring. So I have some questions on the semester final he gave me that I’m stuck on.

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The Ka for HF is 7 E-4, and Ksp for PbF2 is 4 E-8. What is the approximate Kc for the reaction? 2HF + Pb+2 <-- --> PbF2 + 2H- . All are aqueous except PbF2 is solid.

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We have a reversible reaction: 2SO2 + O2 <-- --> 2SO3. All are gases.
All are put in a container so that each has a partial pressure of 1.0 atm. At equilibrium, the partial pressure of the product is 1.33 atm. What is Kp of this process?

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What is the maximum amount of KCl that can be added to a 50.0 ml sample of 0.200 M Pb(NO3)2 solution before a precipitate forms? Ksp of PbCl2 is 1.3 E-5.

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