Answer:

Explanation:
Hello,
In this case, for the dissociation of calcium fluoride:

The equilibrium expression is:
![Ksp=[Ca^{2+}][F^-]^2](https://tex.z-dn.net/?f=Ksp%3D%5BCa%5E%7B2%2B%7D%5D%5BF%5E-%5D%5E2)
In such a way, via the ICE procedure, including an initial concentration of calcium of 0.01 M (due to the calcium nitrate solution), the reaction extent
is computed as follows:

Thus, the molar solubility equals the reaction extent
, therefore:

Regards.
Answer: 
Explanation:
Geometrical symmetry of the molecule and the polarity of the bonds determine the polarity of the molecule.
The molecule that has zero dipole moment that means it is a geometrically symmetric molecule and the molecule which has some net dipole moment means it is a geometrically asymmetric molecule.
As the molecule is symmetric, the dipole moment will be zero as dipole moments cancel each other and the molecule will be non-polar.
As the molecule is asymmetric, the dipole moment will not be zero and the molecule will be polar.
Example: 
Thus, we can say that
is a polar molecule.
The fifth shell can hold up to 50 electrons and the forth shell can hold 8 electrons