I think the correct answer from the choices listed above is the last option. The formula for phosphorous acid is H3PO3. It <span>also called orthophosphorous acid, one of several oxygen acids of phosphorus, used as reducing agent in chemical analysis. Hope this answers the question.</span>
Solubility
product constants are values to describe the saturation of ionic compounds with
low solubility. A saturated solution is when there is a dynamic equilibrium
between the solute dissolved, the dissociated ions, the undissolved and the
compound. It is calculated from the product of the ion concentration in the
solution. For the base, Ca(OH)2, the dissociation would be as
follows:<span>
Ca(OH)2 = Ca2+ + 2OH-
So, the expression for the solubility product constant would be as follows:
Ksp = [Ca2+] [OH-]^2
let x be the concentration of the Ca2+. So,
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Ksp = [x] [2x]^2
<span>Ksp = 4x^3
You have to substitute the value of the concentration of the calcium hydroxide in the final expression which is not given in the problem statement in order to evaluate Ksp.
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This is a question about the colligative property known as freezing point depression. Freezing point depression (the amount the normal freezing point of the solvent is decreased) can be calculated with this equation:
ΔT = i Kf<span> m
</span>
Where i (the van't Hoff factor) is the degree of dissociation of the solute, Kf is the freezing point depression constant, and m is the molality of the solution.
Here i = 2 (KCl dissociates into 2 ions, K+ and Cl-), Kf = 1.86 C/m (for water), and m = 0.743m).
ΔT = 2 x 1.86 C/m x 0.743m = <span>2.764C
</span>
That means the freezing point of the solution is 2.764C less than the pure solvent (water), making it 0C - 2.764C = -2.764C.
The bond<span> length in a </span>molecule<span> of </span>KBr<span> is measured to be 282.1 pm, compared with a </span>nonpolar<span> covalent radius sum for K and Br of 310,4. </span>