Here are the energy levels in a fantasy hypothetical hydrogen-like atom. (you cannot use the rydberg constant, 2.18 x 10-18 j, for this problem, therefore). what is the frequency of a photon that is absorbed when an electron goes from level 2 to level 4? energyn = 4 -2.10 x 10-19 jn = 3 -3.20 x 10-19 jn = 2 - 5.20 x 10-19 jn = 1 - 9.80 x 10-19 j

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Answerthis solution will not form a precipitateexplanationsolubility equilbrium:         pbf₂(s)  ⇄ pb²⁺(aq) + 2 f⁻(aq)the solubility product expression is    (we exclude solids from the equilibrium expression).now suppose we have the trial ion product q, which we can define as    then, we can interpret  q as the product of the concentration of the ions that we have and ksp as the product of the ion concentrations that are needed to form a saturated solution.if q > ksp, then that implies that there will be a surplus of ions that exceed the amount that is required to form a saturated solution. a precipitate will then form (the precipitate continually  forms until the surplus ions are removed and q is decreased to ksp's value).if q = ksp, the saturated solution that forms is barely saturated and the precipitate will be minimal.if q < ksp, then the ion concentration will not be enough to form a saturated solution (so no precipitate).using our information, we calculate the trial ion product:     since q = 2.7  × 10⁻⁸ < ksp =  4  ×  10⁻⁸, a precipitate will not form.

Qand k are only the same when the forward rate of the reaction has reached zero.