A. First ionization energy and reactivity
B. melting point and atomic radius
C. Reactivity and electronegativity
D. First ionization energy and melting point
Correct Answer:
Option D – First ionization energy and melting point
Explanation
– The ionization energy of an atom is the amount of energy that is required to remove an electron from a mole of atoms in the gas phase:
– It is possible to remove more electrons from most elements, so this quantity is more precisely known as the first ionization energy, the energy to go from neutral atoms to cations with a 1+ charge.
– The ionization energy decreases from top to bottom in groups, and increases from left to right across a period.
– The boiling and melting points decrease as you move down the group.