The table provided gives the densities of four transparent materials A student has a clear block of an unknown substance and needs to determine the identity of the substance. The mass of the block is 23.9 grams. The block displaces 8.8 mL of water when dropped in a graduated cylinder. What is the
identity of the substance?
Substance
Density
Polyethylene
0.85 g/ml
Lucite
1.2 g/mL
Glass
2.3 g/mL
Quartz
2.7 g/ml
Polyethylene
Lucite
Glass
Quartz

"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."

the objects have the same charge is correct.

nathan lee