Essay on Periodic Trends

Answer: The atomic radius of an element is the average or typical distance from its center to the boundary of the surrounding electron cloud.

Ans: The trend of the atomic radius over a period, in this case the period 2, the radius decreases, because the number of orbits is stable, but the number of electrons that increases the number of protons is "closer" gravitational force Because it makes

As the whole track is added to the next step, the trend of the atomic radius of the group, in this case group 1, is the increase in radius.

Ans: The density trend in the second and third period is that the density increases to the third group, decreases to the fifth group, increases to the seventh group, and the density of the group decreases .

Answer: Electronegativity is the tendency to attract electrons when atoms form ionic bonds. Electron affinity refers to the energy released when electrons are obtained, whether it is heat or light.

Ans: As valence increases due to increasing valence except for inert gases that do not need to attract other electrons at stable atoms, electronegativity increases from left to right as time passes.

A: When moving from left to right, the number of protons in the core increases, so the electron affinity increases.

The period is the horizontal line of the periodic table. Groups generally have a more pronounced periodic tendency, but the elements of the lanthanides and acts form two elementary levels of the element series, like the f-block, the horizontal trend is a vertical group Trend is more important. Elements with the same period show the trend of atomic radius, ionization energy, electron affinity and electronegativity. Moving from left to right over a period of time, the atomic radius usually decreases. This occurs because there are additional protons and electrons in each successive element. This attracts electrons close to the core. This decrease in atomic radius also increases as the ionization energy moves from left to right over a period of time. The more closely the elements are combined, the more energy is needed to remove the electrons. Electronegativity increases in the same way as ionization due to the pulling force applied to electrons

The general trend of ionization energy is to increase by group and to increase from left to right. Since elements that are abnormally involved appear continuously in the periodic table, a tendency of "from left to right" can be seen. The reason for this tendency depends on Zeff. As the number of protons in the nucleus increases, Zeff increases. The more protons in the nucleus, the greater the attraction between a single electron and the nucleus. In other words, the higher the Zeff.Zeff, the closer the electron is to the nucleus and the more energy it needs. Please separate these electrons from atoms. However, in some cases, this trend does not apply to specific elements. Regarding the tendency of the ionization energy of the periodic table, the following abnormality occurs.