Place the atoms relative to each other. Place the atom with group number in the center because it has the electronegativity. If atoms have the same group number, place the atom with the period number in the center.

Place the atoms relative to each other. Place the atom with lower group number in the center because it has the lower electronegativity. If atoms have the same group number, place the atom with the higher period number in the center.

Explanation:

Generally, electronegativity increases from left to right within a period (horizontal rows in the periodic table), and decreases from top to bottom within a group (vertical columns).

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).

since electrons are negative the answer is neagtaive