Periodic Trends Are Specific Patterns That Are Present

1399 WordsAug 19, 20156 Pages
Periodic trends are specific patterns that are present in the periodic table they illustrate different aspects of a certain element, including its size and its properties. Major periodic trends include: • Electronegativity • Ionization energy • Electron affinity • Atomic radius • Melting point • Metallic character Periodic trends, arising from the arrangement of the periodic table, provide chemists and scientists with a helpful tool to quickly 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. Electronegativity Trends The definition of electronegativity is how strongly an atom can…show more content…
On the left hand side of the periodic table the elements have a half-full valance shell, so meaning that it is a higher energy level to gain electrons to fill that valance shell compared to less energy to lose the electrons to complete the valance shell. Element on the left side usually lose electrons to form a bond. Therefor elements on the right side are more energy efficient in gaining a set of electrons to fill the valance shell. In a periodic table from left to right across a period, electronegativity increases. If the valance shell is less than half full the atom loses electrons to balance out and the opposite if the atom has a valance shell over half full. In a group from top to bottom electronegativity decreases. There is an important exception noble gases, lanthanides, and actinides do not have electronegativity principles, this is because they have a full valance shell so they do not usually attract electrons. And as for transition metals, even though they have electronegativity values, they are little different going up and down a group and going across a period. This is because of the transition metals, metallic properties which affect their ability to attract electrons. Ionisation Energy Trends Ionisation energy is defined as the energy required for the removal of an electron from a neutral atom in its vaporous phase. In theory, ionisation energy has to opposite characteristic to
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