Determine the value of the equilibrium constant (report
youranswer to three significant figures) for the following reaction
ifan equilibrium mixture contains 0.010 mol of solid
pbi2,and is 0.0100 m in pb2+ ions and 0.00081
m ini1- ions. use the notation 4.31e-5 to indicate a
numbersuch as 4.31 x 10-5.

Kps = 6.56e⁻⁹

Explanation:

This is a solubility equilibrium

PbI₂  (s)  ⇄  Pb²⁺  +  2I⁻

Expression for Kc will be:

[I⁻]²  . [Pb²⁺] / [PbI₂]

But we do not have to consider the solid. It does not have a physical sense.  Amount of solid without dissolving, doesn't affect the ions concentrations.

We talk about Kps (Constant for solubility product)

Kps = [I⁻]²  . [Pb²⁺]

Kps = (0.00081)²  .  0.01 → 6.56x10⁻⁹

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.

it’s previous models   because when i picked that son of a gun’s answer it was wrong look for previous models because they might make it a different letter