Bromine attracts electrons more strongly. Cesium is In fact the least electro negative element.
Sodium is more likely to lose an electron because is is less electro negative. Strong electronegativity make the element want more electrons. Sodium has loose electrons with a lower electronegativity so it gives it up easier.
A valid Lewis structure of IF3 cannot be drawn without violating the octet rule.
Answer: IF3 (Iodine Trifluoride)
This is because, I (Iodine) and F (Fluorine) both have odd number of valence electrons (7) which also means that there are too many valence electrons in the valence shell.
The average atomic weight is, from the name itself, the average weight of all its naturally occurring isotopes. All you have to do is multiple the abundance of each isotope with its individual mass, then add them altogether.
Mass = (0.10*55)+(0.15*56)+(.75*57)
<em>Mass = 56.65 amu</em>
