Answer:
The expression of an equilibrium constant will given as:
![K_c=\frac{[NH_3]^2}{[N_2][H_2]^3}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B%5BNH_3%5D%5E2%7D%7B%5BN_2%5D%5BH_2%5D%5E3%7D)
Explanation:
Equilibrium constant is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios. It is expressed as 
K is the constant of a certain reaction when it is in equilibrium

The expression of an equilibrium constant will given as:
![K_c=\frac{[NH_3]^2}{[N_2][H_2]^3}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B%5BNH_3%5D%5E2%7D%7B%5BN_2%5D%5BH_2%5D%5E3%7D)
-0° freezing point ice or ice cream
Answer:
XY4Z2 ----- square planar
XY5Z ------- square pyramidal
XY2Z----- bent < 120°
XY2Z3 ----- Linear
XY4Z ---- see saw
XY2Z2 ----- bent <109°
XY3Z2 ----- T shaped
XY3Z ----- Trigonal pyramidal
Explanation:
The valence shell electron pair repulsion theory ( VSEPR) gives the description of molecular geometry based on the relative number of electron pairs present in the molecule.
However, electron pairs repel each other, the repulsion between two lone pairs is greater than the repulsion between a lone pair and a bond pair which is also greater than the repulsion between two lone pairs.
The presence of lone pairs distort the bond angle and molecular geometry from the expected geometry based on VSEPR theory. Hence, in the presence of lone pairs of electron, the observed molecular geometry may be different from that predicted on the basis of the VSEPR theory, the bond angles also differ slightly or widely depending on the number of lone pairs present.
All the molecules in the question possess lone pairs, the number of electron pairs do not correspond to the observed molecular shape or geometry due to lone pair repulsion. Usually, the molecular geometry deals more with the arrangement of bonded atoms in the molecule.