Respuesta :
Answer:
(d) Cl, Br, Se
Explanation:
Ionisation energy is defined as the minimum energy required to remove the loosely bound valence electron of a neutral gaseous atom or molecule. It is usually endothermic process.
Accorfing to the trends down the group and across the period:
Ionisation energy generally increases as one moves from left to right in a given period while ionisation generally decreases as one moves from top to bottom in a given group. This is of the magnitude of the effective Nuclear charge and the Number of electron shells.
From the elements above:
Ionisation energy decreases down the group while it increases across the period.
F > C > Be
Li > Na > K
Ar > Cl > Na
Cl > Br > Se
