Trend of electronegativity [ENDORSED]

[Xiang Li 2F]

Hi everyone!
I want to ask what(and why) is the trend of electronegativity down a group in the periodic table? And what about across a period?
Thanks a lot!

[Maia V 1L]

Down a group the electronegativity decreases because the atomic radius is increasing, so the valence electrons aren't as strongly attracted to the nucleus. Across a period electronegativity increases because there are more protons in the nucleus as you go across, causing the nuclear charge to increase, so the electrons are more strongly attached to the nucleus.

[Joseph Ettipio]

Following that logic, the most electronegative atom is fluorine, and the least electronegative would be either cesium or francium.

[Tristan Friet 3G]

Electronegativity decreases down a group, and increases across a period.

[gwenkelley3L]

Electronegativity decreases as we move down the periodic table but increases as we go across, as the atomic radius of each element increases or decreases.

[Edmond Chu 1C]

Electronegativity decreases down a group and increases across a period. Electronegativity the the degree to which an element tends to gain electrons. Electronegativity will inrease across a period because it will want 8 electrons in its outer shell and will want more electrons as it increases across a period. Electronegativity decreases down a group because the atomic radius is increasing so there is less attraction between electrons and protons.

[Daniel Li 3C]

Electronegativity increases as you move across a period. In contrast, electronegativity decreases as you move down a group. This is due to the atoms across the period wishing to get to an octet. Electronegativity decreases down a group because there are more and more shells and the atom is bigger, so there is less attraction.

[Skylar Lo 2C]

Electronegativity decreases as you move down a group due to increasing atomic radius. Electronegativity across a period increases because electrons are more strongly attached to the nucleus.