Solid silver acetate is slowly added to 175 mL of a 0.0407 M potassium phosphate solution. The concentration of silver ion required to just initiate precipitation is Solid sodium hydroxide is slowly added to 50.0 mL of a 0.0328 M chromium(III) acetate solution. The concentration of hydroxide ion required to just initiate precipitation is
Solid barium nitrate is slowly added to 150 mL of a 0.0566 M ammonium fluoride solution. The concentration of barium ion required to just initiate precipitation is

"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."

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.

the answer your looking for is c).

i believe the answer is 5,000