Choose the strongest acid. acid a, ka = 2.3 x 10-8 acid b, ka = 2.5 x 10-6 acid c, ka = 8.3 x 10-7 acid d, ka = 1.4 x 10-7

The strength of an acid can be predicted from its acid dissociation constant.

For a hypothetical monoprotic acid HA, the dissociation equilibrium is:

HA ↔ H+ + A-

Ka = [H+][A-]/[HA]

Now, higher the Ka value, greater is the dissociation and stronger is the acid strength

Based on the given examples, Ka is the highest for Acid B= 2.5 * 10⁻⁶. Hence Acid B is the strongest acid.

Ans: Acid B

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."