Sort the following elements by electron affinity, from most positive to most negative EA value: bismuth, chlorine, helium, cesium, and tellurium.

Answer 1

Here is a site that has the electron affinity of each element. Click on the element and scroll down the menu on the left side of the screen to electronic properties, then to electron affinity.
http://www.webelements.com/webelements/elements/text/Mo/key.html