Which element is more electronegative?

[Arielle Kunitz 3A]

Would Oxygen or Chlorine be considered more electronegative? I understand that the trend states that as you move up and across, from left to right, the periodic table, the more electronegative the element is, with Fluorine being the most electronegative. However, Oxygen is directly to the left and Chlorine is directly below Fluorine...
So, which element is more electronegative?
Thanks so much,
Arielle Kunitz

[Jeannie Huang 3B]

Oxygen is more electronegative than chlorine. It has an electronegativity unit of 3.5 while chlorine is 3.0. But I'm fairly certain we only need to know the general trend and not specific details like this.

http://butane.chem.uiuc.edu/cyerkes/chem102ae_fa08/homepage/Chem102AEFa07/Lecture_Notes_102/Lecture%2012%20_files/image24.gif