21. Which element is most electronegative? Helium Hydrogen Flourine Aluminum Other:

## Step 1<br />Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons. The higher the electronegativity, the more an atom or ion attracts electrons towards itself.<br />## Step 2<br />The Pauling scale is used to measure electronegativity. The higher the value on the Pauling scale, the more electronegative the element is.<br />## Step 3<br />According to the Pauling scale, Fluorine has the highest electronegativity, with a value of 3.98. This means that Fluorine has the greatest tendency to attract electrons towards itself.