Question

which pair of elements is most likely to form an ionic bond?

A:hydrogen and helium
B:lithium and potassium
C:potassium and iodine
D:iron and zinc

Answer 1

The difference in 'electronegativity' needs to be great to form an ionic bond, or in other words, you need an element that desperately wants an electron (high electronegativity) and an element that wants to give an electron (low electronegativity) so assuming you know how to draw out the dot structures of elements or 'bhors model' we can draw it out for potassium and iodine;


K loses an electron I gains it. (ionic bond). trend; electronagativity increases as you go from the bottom left of the periodic table to the top right excluding the noble gasses because they are stable. http://www.chemistry-reference.com/pdictable/electronegativity%20table.jpg