Electronegativity increases as you move from left to right across a period on the periodic table. This is because, even though there are the same number of energy levels, there are more positive protons in the nucleus, creating a stronger pull on the negative electrons in the outer shell.Click to see full answer. Beside this, what trend in atomic radius occurs across a period on the periodic table what causes this trend?Atomic radius decreases from left to right within a period. This is caused by the increase in the number of protons and electrons across a period. One proton has a greater effect than one electron; thus, electrons are pulled towards the nucleus, resulting in a smaller radius.Also Know, does electronegativity increase across a period? It is no wonder the electron pair gets dragged so far towards the chlorine that ions are formed. Electronegativity increases across a period because the number of charges on the nucleus increases. That attracts the bonding pair of electrons more strongly. Correspondingly, what causes the electronegativity trend? Electronegativity increases as you move across the periodic table from left to right. This occurs due to a greater charge on the nucleus, causing the electron bonding pairs to be very attracted to atoms placed further right on the periodic table. Fluorine is the most electronegative element.What defines the trends in the periodic table?Periodic trends are specific patterns in the properties of chemical elements that are revealed in the periodic table of elements. Major periodic trends include electronegativity, ionization energy, electron affinity, atomic radii, ionic radius, metallic character, and chemical reactivity.