pH and equilibrium problems

Question

Which of the following would be more soluble in an acid solution a) LiBr(s) or b) KNO3(s)?

What is the pH of a saturated solution of Ni(OH)2(aq) at 25 degrees Celsius?

What is true about the following reaction at 25 degrees Celsius? HBrO+NaCl=NaBrO+HCl

K>1 or K<1?

Answer 1

J.R. pretty much answered the first two questions for you, but here is the answer to the 3rd question:

What is true about the following reaction at 25 degrees Celsius? HBrO+NaCl ↔ NaBrO+HCl

K>1 or K<1?

In this reaction as written, the acid on the reactant side is weak (HBrO) and the acid on the product side is strong (HCl). However, in general, stronger acids/bases react to form weaker acids/bases (their weaker conjugates).

This reaction would not tend to go in the forward direction, the reverse reaction is favored.

So the K value for this reaction as written will be small (K<1)

Answer 2

Since LiBr and KNO₃ are both salts of strong acids, they are both soluble.

Br^- + H2O ==> HBr +OH-

NO₃^- + H2O ==> HNO₃ + OH^-

Ni(OH)₂(s) ==> Ni²⁺(aq) + 2OH^-(aq)

Ksp = [Ni²⁺][OH^-]²

Look up the Ksp of Ni(OH)₂ and the solubility. Plug these values into the Ksp expression. Solve for [OH^-]. Take negative log to get pOH. Subtract from 14 to get pH

There is no way to tell if K is > or < 1 without additional information unless you are suggesting that HCl being strong will ionize pushing reaction to right and then K would be > 1. But there sre too many other factors for this to ne absolute.