what are the group and period trends for electronegativity
Periodic trends Periodic trends are specific patterns that are present in the periodic table that illustrate different aspects of a certain element, including its radius and its electronic properties. Major periodic trends include: electronegativity, ionization energy, electron affinity, atomic radius, melting point, boiling point, metallic character, ionic radius and reactivity. Periodic trends arise from the arrangement of elements in the periodic table and allow chemists to quickly and reliably predict an element's properties. These trends exist because of the similar atomic structure of the elements within their respective group families or periods, and because of the periodic nature of the elements. There are exceptions to these trends, such as that of ionization energy in Groups 3 and 6.
Period 4 element A period 4 element is one of the chemical elements in the fourth row (or period) of the periodic table of the elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour begins to repeat, meaning that elements with similar behaviour fall into the same vertical columns. The fourth period contains 18 elements, beginning with potassium and ending with krypton. As a rule, period 4 elements fill their 4s shells first, then their 3d and 4p shells, in that order; however, there are exceptions, such as chromium.