The overall molecule is Polar because the shape of the molecule is Trigonal Pyramidal, which means it has the lone pair electrons. Becuase of the lone pair the pulling is unequal.
H3O+ has 3 polar bonds.
To know if the bonds are polar or nonpolar find the difference of the element's electronegativity charge.
H has electronegativity charge of 2.2, and O has 3.4.
Always subtract the smaller number from the greater one.
So 3.4 - 2.2 = 1.2
If the difference is from 0-0.4 the bond is nonpolar, but if it's from 0.5-1.9 the bond is polar.
So, 1.2 is polar bond. So H3O+ has 3 polar bonds, and the overall molecule is polar too.
A simple way to know if it's polar or nonpolar is to draw the lewis dot structure, and use VSEPR.
Answer:
D H2PO4– + HPO42–
Explanation:
The acid dissociation constant for
are
respectively.



The reason while option D is the best answer is that, the value of pKa for both
lies on either side of the desired pH of the buffer. This implies that one is slightly over and the other is slightly under.
Using Henderson-Hasselbach equation:

The population decreases when the birth rate is less than the death rate.
At room temperature hydrogen chloride is a colorless gas with a sharp or pungent odor. Under pressure or at temperatures below –85°C (-121°F), it is a clear liquid.